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Aplicação do método k0-INAA no Laboratório de Análise por Ativação com Nêutrons do IPEN utilizando o programa k0-IAEA. Análise de amostras biológicas. / k0-INAA application at IPEN Neutron Activation Laboratory by using the k0-IAEA program. Biological sample analysisDaniel Correa Puerta 14 June 2013 (has links)
Este estudo apresenta os resultados obtidos na aplicação do método de padronização k0-INAA no LANIPEN, para a análise de amostras biológicas, utilizando o programa k0-IAEA, fornecido pela Agência Internacional de Energia Atômica (IAEA). Os parâmetros de fluxo f e α do reator IEA-R1 do IPEN foram determinados na estação pneumática de irradiação e na posição de irradiação 24B/prateleira2, para irradiações curtas e longas, respectivamente. Para obter esses fatores, foi utilizado o chamado método bare triple-monitor com 197Au-96Zr- 94Zr. Para a verificação da precisão e exatidão do método, foram analisados os materiais biológicos de referência Peach Leaves (NIST SRM 1547), Mixed Polish Herbs (INCT-MPH-2) e Tomato Leaves (NIST SRM 1573a). Os critérios estatísticos Erro Relativo (bias, %), Coeficiente de Variação (CV) e U-score foram aplicados para avaliação dos resultados obtidos (média de seis replicatas). Os erros relativos (bias, %) ficaram, para maioria dos elementos, entre 0 e 30%, em relação aos valores certificados. Os Coeficientes de Variação foram inferiores a 20%, mostrando boa reprodutibilidade nos resultados obtidos experimentalmente. Os valores de U-score mostraram que todos os resultados, com exceção do valor para Na no Peach Leaves e no Tomato Leaves, estão dentro de um intervalo de confiança de 95%. Estes resultados apontam para uma promissora utilização do método k0-INAA no LAN-IPEN para a análise de amostras biológicas. / The results obtained in the application of the k0-standardization method at LAN-IPEN for biological matrices analysis, by using the k0-IAEA software, provided by the International Atomic Energy Agency (IAEA), are presented. The flux parameters f and α of the IEA-R1 reactor were determined for the pneumatic irradiation facility and for one selected irradiation position, 24B/shelf2, for short and long irradiations, respectively. In order to obtain these parameters, the bare triple-monitor method with 197Au-96Zr-94Zr was used. In order to evaluate the accuracy and precision of the methodology, the biological reference materials Peach Leaves (NIST SRM 1547), Mixed Polish Herbs (INCT-MPH-2) e Tomato Leaves (NIST SRM 1573a) were analyzed. The statistical criteria Relative Errors (bias, %), Coefficient of Variation (CV) and U-score were applied to the obtained results (mean of six replicates). The relative errors (bias, %) in relation to certified values, were, for most elements, in the range of 0 e 30. The Coefficients of Variation were below 20%, showing a good reproducibility of the results. The Uscore test showed that all results, except Na in Peach Leaves and in Tomato Leaves, were within 95% confidence interval. These results point out to a promising use of the k0-INAA method at LAN-IPEN for biological sample analysis.
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Aplicação do método k0-INAA no Laboratório de Análise por Ativação com Nêutrons do IPEN utilizando o programa k0-IAEA. Análise de amostras biológicas. / k0-INAA application at IPEN Neutron Activation Laboratory by using the k0-IAEA program. Biological sample analysisPuerta, Daniel Correa 14 June 2013 (has links)
Este estudo apresenta os resultados obtidos na aplicação do método de padronização k0-INAA no LANIPEN, para a análise de amostras biológicas, utilizando o programa k0-IAEA, fornecido pela Agência Internacional de Energia Atômica (IAEA). Os parâmetros de fluxo f e α do reator IEA-R1 do IPEN foram determinados na estação pneumática de irradiação e na posição de irradiação 24B/prateleira2, para irradiações curtas e longas, respectivamente. Para obter esses fatores, foi utilizado o chamado método bare triple-monitor com 197Au-96Zr- 94Zr. Para a verificação da precisão e exatidão do método, foram analisados os materiais biológicos de referência Peach Leaves (NIST SRM 1547), Mixed Polish Herbs (INCT-MPH-2) e Tomato Leaves (NIST SRM 1573a). Os critérios estatísticos Erro Relativo (bias, %), Coeficiente de Variação (CV) e U-score foram aplicados para avaliação dos resultados obtidos (média de seis replicatas). Os erros relativos (bias, %) ficaram, para maioria dos elementos, entre 0 e 30%, em relação aos valores certificados. Os Coeficientes de Variação foram inferiores a 20%, mostrando boa reprodutibilidade nos resultados obtidos experimentalmente. Os valores de U-score mostraram que todos os resultados, com exceção do valor para Na no Peach Leaves e no Tomato Leaves, estão dentro de um intervalo de confiança de 95%. Estes resultados apontam para uma promissora utilização do método k0-INAA no LAN-IPEN para a análise de amostras biológicas. / The results obtained in the application of the k0-standardization method at LAN-IPEN for biological matrices analysis, by using the k0-IAEA software, provided by the International Atomic Energy Agency (IAEA), are presented. The flux parameters f and α of the IEA-R1 reactor were determined for the pneumatic irradiation facility and for one selected irradiation position, 24B/shelf2, for short and long irradiations, respectively. In order to obtain these parameters, the bare triple-monitor method with 197Au-96Zr-94Zr was used. In order to evaluate the accuracy and precision of the methodology, the biological reference materials Peach Leaves (NIST SRM 1547), Mixed Polish Herbs (INCT-MPH-2) e Tomato Leaves (NIST SRM 1573a) were analyzed. The statistical criteria Relative Errors (bias, %), Coefficient of Variation (CV) and U-score were applied to the obtained results (mean of six replicates). The relative errors (bias, %) in relation to certified values, were, for most elements, in the range of 0 e 30. The Coefficients of Variation were below 20%, showing a good reproducibility of the results. The Uscore test showed that all results, except Na in Peach Leaves and in Tomato Leaves, were within 95% confidence interval. These results point out to a promising use of the k0-INAA method at LAN-IPEN for biological sample analysis.
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Tunable Patch Antenna Using Semiconductor and Nano-Scale Barium Strontium Titanate VaractorsBaylis, Samuel Andrew 23 March 2007 (has links)
Patch antennas are fundamental elements in many microwave communications systems. However, patch antennas receive/transmit signals over a very narrow bandwidth (typically a maximum of 3% bandwidth). Design modifications directed toward bandwidth expansion generally yield 10% to 40% bandwidth.
The series varactor tuned patch antenna configuration was the bandwidth enhancement method explored in this research; this configuration is implemented by dividing a patch antenna into multiple sections and placing varactors across the resultant gaps. In addition to yielding a large bandwidth, the configuration has a number of ancillary benefits, including straightforward integration and design flexibility. Through the research represented by this work, the properties of the series varactor tuned patch antenna, herein referred to as the Fragmented Patch Antenna (or FPA), were explored and optimized. As a result, an innovative patch antenna was produced that yielded 63.4% frequency tuning bandwidth and covered a frequency range between 2.8 and 5.4 GHz. The wide bandwidth was achieved through a detailed parametric study. The products of this study were the discovery of multiple tuning resonances that were used to expand the tuning bandwidth and the understanding/documentation of the significance of specific antenna dimensions.
Measurement results were obtained through the fabrication of a prototype antenna using semiconductor varactors.
In the second research phase, the construction of capacitors using the tunable permittivity material Barium Strontium Titanate (BST) was investigated. Using this material in conjunction with nano-fabrication techniques, varactors were developed that had good estimated performance characteristics and were considered appropriate for integration into adaptive microwave circuitry, such as the tunable antenna system.
The varactors were constructed by using Focused Ion Beam (FIB) milling to create a nano-scale capacitive gap in a transmission line. A combination of end-point current detection (EPD) and cross-section scanning electron (SEM) and ion beam (FIB) microscope images were used to optimize the milling procedure. The future extensions of this work include the integration of the BST varactors with the antenna design; the configuration of the developed BST varactors lends itself to a straightforward integration with the FPA antenna.
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Development and performance assessment of ITER diagnostics for runaway electrons based on predictive modelling / Conception et évaluation des performances des diagnostics de mesure des électrons découplés pour ITER fondé sur une modélisation prédictivePandya, Santosh 19 March 2019 (has links)
Dans les tokamaks, Sous l'application champ de électrique, les électrons sont accélérés et en même temps, ils subissent une force de friction due aux collisions avec les autres particules du plasma. Cependant, une fraction de la population totale d'électrons peuvent surmonter la force de friction et atteindre une vitesse proche de la vitesse lumière. Ces électrons relativistes sont découplés du plasma et sont appelés électrons runaway (ER). Ils peuvent apparaître lors des différentes phases d'une décharge de plasma. Par exemple, dans la phase de démarrage ou alors pendant les disruptions, au cours desquelles une fraction importante du courant plasma peut être convertie en ER ayant une énergie pouvant atteindre quelques dizaines de MeV. Les ER créés pendant la phase de perturbation peuvent causer des dommages aux premiers composants murs si un dépôt localisé de forte puissance se produit. ITER étant un tokamak de grande taille et un projet coûteux, la génération d'ER n'est pas souhaitable. La viabilité de la machine nécessite que les ER soient détectés en temps réel. La thèse fournit une étude détaillée dans cette direction pour le développement des deux principaux diagnostics sur ITER impliqués dans les mesures de paramètres pour les ER, à savoir, le moniteur de rayons X durs qui détecte le rayonnement de bremsstrahlung et les caméras visibles et infrarouges qui détectent le rayonnement synchrotron. Une solution de conception unique a été proposée pour le moniteur HXRM et est développée ici et optimisée. Pour les caméras, une modélisation des signaux est effectuée pour la première fois. Pour ce faire, un code de calcul a été développé et validé sur différents tokamaks. / In tokamaks, under the application of the electric field, a small fraction of the total electrons population can overcome collisional drag force and attain high velocity close to the speed of light. These relativistic electrons are called Runaway-Electrons (REs). The REs can occur during different phases of a plasma discharge. REs created during the disruptions phase can form a high energetic RE-beam that poses a risk to damage the first wall components if localized high power deposition takes place. ITER being a large size tokamak and an expensive project, generation of REs is not desirable during any phases of a plasma discharge. Detection of these REs and measurements of its parameters are important for the tokamak operation. Hence, RE diagnostics have to be in place to aid the commissioning of the disruption mitigation system and also for the post-event analysis to improve the reliability of RE avoidance. The present thesis gives a detailed study in this direction for the development of the two principal ITER Diagnostics involved in RE parameter measurements, namely the Hard X-Ray Monitor (HXRM) that detects bremsstrahlung radiation and the Visible and Infrared Cameras that detect synchrotron radiation. A unique design solution has been given for the HXRM and is developed, R&D tests were performed and optimized in line with this understanding. For the cameras, it is predicted for the first time which images and signal intensity can be expected. To achieve this, a simple but comprehensive code has been developed and validated on tokamaks that can predict RE parameters and corresponding diagnostic signals which may have further uses also in the context of RE avoidance.
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Hardware and Software Improvements to a Low-Cost Holographic Video MonitorHenrie, Andrew August 01 June 2018 (has links)
The "Mark V" Holographic Video Monitor ("HoloMonitor") is a continuation of effort and accomplishments to produce a low-cost device capable of reproducing true full-color horizontal-parallax-only computer-generated holograms at typical video frame-rates. While other devices around the world may have greater capabilities, these devices are currently confined to laboratory settings due to their sheer complexity and expense. The aim of this project is to provide researchers and "tinkerers" with a device capable of recreating holographic effects in full color, respectable resolution, in real time, and at a comparatively low cost. The "Mark V" HoloMonitor is a closer representation of a consumer product than any other device of the MIT/BYU series of HoloMonitors. In this thesis, I discuss the complete design and construction of all of the optic (sans modulator) electronic subsystems that compose this device, along with explaining and providing working code needed to drive it in various modes of operation. The main objective of this thesis is to sufficiently instruct undergraduate and graduate colleagues so that they can replicate and build upon this work.
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Impact of wildfire on the spotted-tailed quoll Dasyurus maculatus in Kosciuszko National ParkDawson, James Patrick, Physical, Environmental & Mathematical Sciences, Australian Defence Force Academy, UNSW January 2005 (has links)
A population of spotted-tailed quolls Dasyurus maculatus was studied for three years (2002-2004) in the lower catchment of the Jacobs River, in the Byadbo Wilderness Area of southern Kosciuszko National Park, south-eastern New South Wales, Australia. Survey and monitoring of quoll latrine sites and prey populations, dietary analysis and live-trapping was carried out for one year before and two years after the widespread wildfires of January 2003, which had a very high impact on the study area. Survey for spotted-tailed quoll latrine sites was successful in locating a total of 90 latrine sites in the Jacobs River study area over the three years of the study. These were found throughout all parts of the topography among large, complex granite outcrops and along rocky sections of riparian habitat. After the fire in 2003, lower numbers of latrines were in use than observed pre-fire, and there was a lower level of usage (number of scats) of individual latrines. Continued monitoring in 2004 revealed that many latrines that had become inactive in 2003 following the fire were re-activated in the second breeding season following fire. 1466 spotted-tailed quoll scats were collected from latrines and live-trapped quolls over the three years of the study. Hair analysis from scats identified twenty-two different species of mammal in the diet of the spotted-tailed quoll from the Jacobs River study area, representing the majority of all prey identified (98.5% occurrence) and contributing almost all of the biomass consumed (99.6%). Medium-sized mammals were the most important prey category, followed by small mammals, large mammals (most likely taken as carrion) and non-mammalian prey (birds, reptiles, insects and plants). Brushtail possums were the most important single prey item by both frequency of occurrence and percentage biomass in all years, followed by lagomorphs (rabbits and hares), Rattus spp., and swamp wallabies. There was a significant difference in the composition of the diet by major prey category across the years of the study as a result of the fire, indicated by a shift in utilisation of food resources by quolls in response to significant changes in prey availability. Monitoring of prey populations revealed that brushtail possums, lagomorphs and bandicoots were all significantly less abundant in the study area in the winter directly following the fire, followed by a significant increase in abundance of lagomorphs, but not of possums, in the second winter after the fire. Quolls adapted well to this altered prey availability. While there was a significant decrease in occurrence of brushtail possum in scats after the fire, significantly more scats contained hair of lagomorphs, to the point where almost equal proportions of lagomorphs and possum hair occurred in scats by the winter of 2004. Other fire-induced changes to the diet were evident, such as a significant drop in the occurrence of small mammals in scats for both winters after the fire, and a peak in occurrence of large mammals in the winter directly following the fire that strongly suggests there was a short-term increase in the availability of carrion. A large, high-density population of spotted-tailed quolls was live-trapped and marked during the winter breeding season of 2002. Twenty-two quolls (13 male and 9 female) were present in the study area in 2002, and subsequent trapping over the 2003 and 2004 winter breeding seasons following the fire revealed that the high-intensity wildfire did not result in the extinction of the local population. There was evidence of a small, short-term decline in the number of quolls present in the study area in the 2003 breeding season, with 16 individual quolls captured. Males were outnumbered two-to-one by females, due either to mortality or emigration. Trapping in 2004 showed a recovery of the population to numbers exceeding that observed prior to the fire, with 26 individuals captured (16 male, 10 female), most likely as a result of immigration. There was some evidence that recruitment of young from the post-fire breeding season in 2003 was reduced because of the fire. This study took advantage of an unplanned wildfire event to monitor the response of a population of spotted-tailed quolls and their prey. In this regard it was fortuitous since it has been recognised that the use of replicates and controls in the study of the impacts of wildfire on such species is likely to be logistically impossible. Consequently, the effects of fire on forest and woodland fauna such as the spotted-tailed quoll are poorly understood, with many authors expressing concern that, potentially, wildfires are likely to be highly detrimental to resident quoll populations. The results of this study, however, concur with the few other studies in which forest mammal populations have been monitored before and after wildfire in suggesting that wildfires may not be as destructive to fauna as that imagined. The results of this work will provide information to assist in the preparation of management strategies for the species, such as recovery plans, as well as information for land managers preparing management plans, including fire management plans, for habitats in which spotted-tailed quolls are found throughout their range.
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Implementing effective school practices for secondary English language learners : implications for leadersHester, Debra Cantu 24 September 2013 (has links)
In 1999, Texas Legislature mandated the Student Success Initiative to ensure all eighth grade students are on grade level in reading and mathematics. Although progress is evident, the achievement gap for English language learners remains. The purpose of this case study was to explore effective school practices that lead to closing the achievement gap. This qualitative study applies the two core functions of leadership for exercising influence and providing direction to answer the research question: How do the core functions of school leadership practices for implementing the Student Success Initiative requirements vary between English language learners and non-English language learners in high and low-performing middle schools? The comparison between the high-performing school and low-performing school brought forth key findings and identifies school practices for supporting secondary English language learners.
The key findings for exercising influence on teachers were: 1) Effective school practices that influence teacher knowledge on how to identify students and their needs include: a) conducts a needs assessment.; b) analyze data; c) create differentiated ESL programs, d) place diverse groups of ELLs in differentiated ESL programs. 2) Effective school practices to influence teachers how to intervene include: a) accept teacher input and follow through on requests when planning interventions, b) target intervention needs; c) create differentiated interventions. 3) Effective school practices to influence teachers how to monitor include: a) analyze multiple types of data, b) measure student reading growth; c) measure student language proficiency, d) conduct walkthroughs to observe students. The key findings for providing direction to teachers established the following practices: 4) Effective school practices to provide direction to identify students and their needs include, a) develop and implement a school wide intervention plan, b) create a master schedule to implement differentiated ESL programs; c) model how to disaggregate data, d) develop and implement an individual plan for ELLs. 5) Effective school practices to provide direction to intervene include: a) assign ESL teacher to intervention groups, b) use data to drive intervention planning, c) measure growth in language and literacy, d) provide daily interventions, e) integrate language and literacy interventions in lessons. 6) Effective school practices to provide direction to teachers for monitoring include: a) measure growth of literacy and language development, b) triangulate multiple types of data, c) review intervention lessons during walkthroughs, e) provide daily interventions specific to student needs. / text
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Intense pulsed neutron generation based on the principle of Plasma Immersion Ion Implantation (PI3) technique.Motloung, Setumo Victor January 2006 (has links)
<p>The development of a deuterium-deuterium/ tritium-deuterium (D-D/ D-T) pulsed neutron generator based on the principle of the Plasma Immersion Ion Implantation (PI3) technique is presented, in terms of investigating development of a compact system to generate an ultra short burst of mono-energetic neutrons (of order 1010 per second) during a short period of time (< / 20&mu / s) at repetition rates up to 1 kHz. The system will facilitate neutron detection techniques, such as neutron back-scattering, neutron radiography and time-of-flight activation analysis.</p>
<p><br />
Aspects addressed in developing the system includes (a) characterizing the neutron spectra generated as a function of the target configuration/ design to ensure a sustained intense neutron flux for long periods of time, (b) the system was also characterised as a function of power supply operating conditions such as voltage, current, gas pressure and plasma density.</p>
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Intrångsdetektering i processnätverk / Intrusion detection in process networksFahlström, Albin, Henriksson, Victor January 2018 (has links)
The threat against industrial networks have increased, which raises the demands on the industries cybersecurity. The industrial networks are not constructed with cybersecurity in mind, which makes these systems vulnerable to attacks. Even if the networks outer protection is deemed sufficient, the system may still be infected. This risk demands an intrusion detection system (IDS) that can identify infected components. An IDS scans all traffic of a point in the network and looks for traffic matching its detections parameters, if a match is made the IDS will send an alarm to the administrators. It can also analyze the network traffic using a behavior based method which means that the IDS will alert administrators if network activity deviates from the normal traffic flow. It is of vital essence that the IDS do not impair with the system, an outage of the industrial process can have a high cost for the industry. This report aims to put forward plans for the implementation of an IDS in one of Mälarenergi AB’s industrial networks, this will be made using the Bro and Snort intrusion detection systems. / Hoten mot industrinätverken har blivit större vilket har ställt högre krav på industriernas cybersäkerhet. Industrinätverk är ofta inte konstruerade med cybersäkerhet i åtanke, vilket har gjort dessa system sårbara mot attacker. Även om nätverkets yttre skydd anses gott går det inte att vara säker på att ett industrinätverk förblir osmittat. Detta ställer krav på någon form av intrångsdetekteringssystem (IDS) som kan upptäcka infekterad utrustning och suspekt datatrafik i nätverket. En IDS skannar alla paket vid en viss punkt i nätverket, om IDS:en upptäcker något paket som matchar med dess signatur kommer den att larma en administratör. IDS:en kan även använda beteendeanalys där den larmar om nätverksaktiviteten avviker från det normala. Det är mycket viktigt att en IDS inte orsakar avbrott i industriprocessen, om en process stannar kan det innebära stora kostnader för industrin. Denna rapport syftar till att lämna ett lösningsförslag på en IDS-implementation till ett av Mälarenergi AB: s processnätverk, lösningen konstruerades med hjälp av IDS:erna Bro och Snort. / <p>Vissa bilder i den elektroniska rapporten har tagits bort av upphovrättsliga skäl. Författarna har bedömt att rapporten är förståelig även utan dessa bilder. </p>
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Development of a beam-based phase feedforward demonstration at the CLIC test facility (CTF3)Roberts, Jack January 2016 (has links)
The Compact Linear Collider (CLIC) is a proposal for a future linear electron--positron collider that could achieve collision energies of up to 3 TeV. In the CLIC concept the main high energy beam is accelerated using RF power extracted from a high intensity drive beam, achieving an accelerating gradient of 100 MV/m. This scheme places strict tolerances on the drive beam phase stability, which must be better than 0.2 degrees at 12 GHz. To achieve the required phase stability CLIC proposes a high bandwidth (>17.5 MHz), low latency drive beam "phase feedforward" (PFF) system. In this system electromagnetic kickers, powered by 500 kW amplifiers, are installed in a chicane and used to correct the phase by deflecting the beam on to longer or shorter trajectories. A prototype PFF system has been installed at the CLIC Test Facility, CTF3; the design, operation and commissioning of which is the focus of this work. Two kickers have been installed in the pre-existing chicane in the TL2 transfer line at CTF3 for the prototype. New optics have been created for the line to take these changes in to account, incorporating new constraints to obtain the desired phase shifting behaviour. Three new phase monitors have also been installed, one for the PFF input and two to verify the system performance. The resolution of these monitors must be significantly better than 0.2 degrees to achieve CLIC-level phase stability. A point by point resolution as low as 0.13 degrees has been achieved after a series of measurements and improvements to the phase monitor electronics. The performance of the PFF system depends on the correlation between the beam phase as measured at the input to the PFF system, and the downstream phase, measured after the correction chicane. Preliminary measurements found only 40% correlation. The source of the low correlation was determined to be energy dependent phase jitter, which has been mitigated after extensive efforts to measure, model and adjust the machine optics. A final correlation of 93% was achieved, improving the theoretical reduction in jitter using the PFF system from a factor 1.1 to a factor 2.7. The performance and commissioning of the kicker amplifiers and PFF controller are also discussed. Beam based measurements are used to determine the optimal correction timing. With a maximum output of around 650 V the amplifiers provide a correction range of ±5.5 ± 0.3 degrees. Finally, results from operation of the complete system are presented. A mean phase jitter of 0.28 ± 0.02 degrees is achieved, in agreement with the theoretical prediction of 0.27 ± 0.02 degrees for an optimal system with the given beam conditions. The current limitations of the PFF system, and possible future improvements to the setup, are also discussed.
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