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Algorithme de positionnement précis en environnement contraint basé sur un récepteur bas-coût GPS/GLONASSCarcanague, Sébastien 26 February 2013 (has links) (PDF)
Le GNSS (Global Navigation Satellite System), et en particulier sa composante actuelle le système américain GPS et le système russe GLONASS, sont aujourd'hui utilisés pour des applications géodésiques afin d'obtenir un positionnement précis, de l'ordre du centimètre. Cela nécessite un certain nombre de traitements complexes, des équipements coûteux et éventuellement des compléments au sol des systèmes GPS et GLONASS. Ces applications sont aujourd'hui principalement réalisées en environnement " ouvert " et ne peuvent fonctionner en environnement plus contraint. L'augmentation croissante de l'utilisation du GNSS dans des domaines variés va voir émerger de nombreuses applications où le positionnement précis sera requis (par exemple des applications de transport/guidage automatique ou d'aide à la conduite nécessitant des performances importantes en terme de précision mais aussi en terme de confiance dans la position -l'intégrité- et de robustesse et disponibilité). D'autre part, l'arrivée sur le marché de récepteurs bas-coûts (inférieur à 100 euros) capables de poursuivre les signaux provenant de plusieurs constellations et d'en délivrer les mesures brutes laisse entrevoir des avancées importantes en termes de performance et de démocratisation de ces techniques de positionnement précis. Dans le cadre d'un utilisateur routier, l'un des enjeux du positionnement précis pour les années à venir est ainsi d'assurer sa disponibilité en tout terrain, c'est-à-dire dans le plus grand nombre d'environnements possibles, dont les environnements dégradés (végétation dense, environnement urbain, etc.) Dans ce contexte, l'objectif de la thèse a été d'élaborer et d'optimiser des algorithmes de positionnement précis (typiquement basés sur la poursuite de la phase de porteuse des signaux GNSS) afin de prendre en compte les contraintes liées à l'utilisation d'un récepteur bas coût et à l'environnement. En particulier, un logiciel de positionnement précis (RTK) capable de résoudre les ambiguïtés des mesures de phase GPS et GLONASS a été développé. La structure particulière des signaux GLONASS (FDMA) requiert notamment un traitement spécifiques des mesures de phase décrit dans la thèse afin de pouvoir isoler les ambiguïtés de phase en tant qu'entiers. Ce traitement est compliqué par l'utilisation de mesures provenant d'un récepteur bas coût dont les canaux GLONASS ne sont pas calibrés. L'utilisation d'une méthode de calibration des mesures de code et de phase décrite dans la thèse permet de réduire les biais affectant les différentes mesures GLONASS. Il est ainsi démontré que la résolution entière des ambiguïtés de phase GLONASS est possible avec un récepteur bas coût après calibration de celui-ci. La faible qualité des mesures, du fait de l'utilisation d'un récepteur bas coût en milieu dégradé est prise en compte dans le logiciel de positionnement précis en adoptant une pondération des mesures spécifique et des paramètres de validation de l'ambiguïté dépendant de l'environnement. Enfin, une méthode de résolution des sauts de cycle innovante est présentée dans la thèse, afin d'améliorer la continuité de l'estimation des ambiguïtés de phase. Les résultats de 2 campagnes de mesures effectuées sur le périphérique Toulousain et dans le centre-ville de Toulouse ont montré une précision de 1.5m 68% du temps et de 3.5m 95% du temps dans un environnement de type urbain. En milieu semi-urbain type périphérique, cette précision atteint 10cm 68% du temps et 75cm 95% du temps. Finalement, cette thèse démontre la faisabilité d'un système de positionnement précis bas-coût pour un utilisateur routier.
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Genetics of Glioma : Transcriptome and MiRNome Based ApprochesSoumya, A M January 2013 (has links) (PDF)
Glioma, the tumor of glial cells, is one of the common types of primary central nervous system (CNS) neoplasms. Astrocytoma is the most common of all gliomas and originates from astrocytic glial cells. Astrocytoma tumors belong to two main categories: benign tumors, comprising of grade I Pilocytic astrocytoma and malignant tumors which diffusely infiltrate throughout the brain parenchyma. Diffusely infiltrating astrocytomas are graded into diffuse astrocytoma (DA; grade II), anaplastic astrocytoma (AA; grade III) and glioblastoma (GBM; grade IV) in the order of increasing malignancy. Patients with grade II astrocytoma have a median survival time of 6 to 8 years after surgical intervention. While the more aggressive grade III (AA) and grade IV (GBM) are together called malignant astrocytomas, the treatment protocols and length of survival are distinctly different between these grades. The median survival time for grade III patients is 2 to 3 years whereas patients with grade IV have a median survival of 12-15 months. GBMs have been further divided into primary GBM and secondary GBM on the basis of clinical and histopathological criteria. Primary GBM presents in an acute de novo manner with no evidence of an antecedent lower grade tumor and it accounts for >90% of all GBMs. In contrast, secondary GBM results from the progressive malignant transformation of a grade II or grade III astrocytoma. The current WHO grading system of astrocytomas is based on the histopathological characteristics of the underlying tumor tissue. Diagnoses by pathologists are dependent on specific histologic features: increased mitosis, nuclear atypia, microvascular proliferation and/or necrosis, which associate with biologically aggressive behaviour (WHO 2007). Though grading based on histology is largely reproducible and well accepted, subjectivity involved and substantial disagreement between pathologists has remained a major concern. Because of inherent sampling problems (mainly due to tumor location in the brain) and inadequate sample size available for histological evaluation, there exists a very high possibility of error in grading.
Recent studies have attempted to characterize the molecular basis for the histological and prognostic differences between grade III and grade IV astrocytoma. While reports have shown the grade specific profile of gene expression, there is no molecular signature that can accurately classify grade III and grade IV astrocytoma samples. In the current work, we have
identified molecular signatures for the accurate classification of grade III and grade IV astrocytoma patients by using transcriptome and miRNome data. The receptor tyrosine kinase pathway is known to be overexpressed in 88% of glioblastoma patients. The expression and activation of the receptors is reported to be deregulated by events like amplification and activating mutations. The aberrant expression of RTKs could also be due to the deregulation of miRNAs, which, in the untransformed astrocytes regulate and fine-tune the levels of the RTKs. In the current study, we have identified that tumor suppressor miRNA miR-219-5p regulates RTK pathway by targeting EGFR and PDGFRα.
Part I. Transcriptome approach: Identification of a 16-gene signature for classification of malignant astrocytomas
In order to obtain a more robust molecular classifier to accurately classify grade III and grade IV astrocytoma samples, we used transcriptome data from microarray study previously performed in our laboratory. The differential regulation of 175 genes identified from microarray was validated in a cohort of grade III and grade IV patients by real-time qRT-PCR. In order to identify the classification signature that can classify grade III and grade IV astrocytoma samples, we used the expression data of 175 genes for performing Prediction Analysis of Microarrays (PAM) in the training set of grade III and grade IV astrocytoma samples. PAM analysis identified the most discriminatory 16-gene expression signature for the classification of grade III and grade IV astrocytoma. The Principal Component Analysis (PCA) of 16-genes astrocytoma patient samples revealed that the expression of 16-genes could classify grade III and grade IV astrocytoma samples into two separate clusters. In the training set, the 16-gene signature was able to classify grade III and grade IV patients with an accuracy rate of 87.9% as tested by additional analysis of Cross-Validated probability by PAM. The 16-gene signature obtained in the training set was validated in the test set with diagnostic accuracy of 89%. We further validated the 16-gene signature in three independent cohorts of patient samples from publicly available databases: GSE1993, GSE4422 and TCGA datasets and the classification signature got validated with accuracy rates of 88%, 92% and 99% respectively. To address the discordance in grading between 16-gene signature and histopathology, we looked at the clinical features (age and survival) and molecular markers (CDKN2A loss, EGFR amplification and p53 mutation) that differ substantially between grade III and grade IV in discordant grade III and grade IV
samples. The grading done by 16-gene signature correlated with known clinical and molecular markers that distinguish grade III and grade IV proving the utility of the 16-gene signature in the molecular classification of grade III and grade IV. In order to identify the pathways that 16 genes of the classification signature could regulate, we performed protein-protein interaction network and subsequently pathway analysis. The pathways with highest significance were ECM (extracellular matrix) and focal adhesion pathways, which are known to be involved in the epithelial to mesenchymal transition (EMT), correlating well with the aggressive infiltration of grade IV tumors. In addition to accurately classifying the grade III and grade IV samples, the 16-gene signature also demonstrated that genes involved in epithelial-mesenchymal transition play key role in distinguishing grade III and grade IV astrocytoma samples.
Part II. miRNome approach
microRNAs (miRNAs) have emerged as one of the important regulators of the interaction network that controls various cellular processes. miRNAs are short non-coding RNAs (mature RNA being 21-22nt long) that regulate the target mRNA by binding mostly in the 3’ UTR bringing about either translational repression or degradation of the target. miRNAs are shown to play key roles in cell survival, proliferation, apoptosis, migration, invasion and various other characteristic features that get altered in human cancers. miRNAs are characterized to have oncogenic or tumor suppressor role and the aberrant expression of miRNAs is reported in multiple human cancer types.
Part A. Genome-wide expression profiling identifies deregulated miRNAs in malignant astrocytoma
With an aim to identify the role of miRNAs in the development of in malignant astrocytoma, we performed a large-scale, genome-wide microRNA (miRNA) (n=756) expression profiling of 26 grade IV astrocytoma, 13 grade III astrocytoma and 7 normal brain samples. Using Significance Analysis of Microarrays (SAM), we identified several differentially regulated miRNAs between control normal brain and malignant astrocytoma, grade III and grade IV astrocytoma, grade III astrocytoma and grade IV secondary GBM, progressive pathway and de novo pathway of GBM development and also between primary and secondary GBM. Importantly, we identified a most discriminatory 23-miRNA expression signature, by using PAM, which precisely distinguished grade III from grade IV astrocytoma samples with an accuracy of 90%. We re-evaluated the grading of discordant
samples by histopathology and identified that one of the discordant grade III samples had areas of necrosis and it was reclassified as grade IV GBM. Similarly, out of two discordant grade IV samples, one sample had oligo component and it was reclassified as grade III mixed oligoastrocytoma. Thus, after the revised grading, the prediction accuracy increased from 90% to 95%. The differential expression pattern of nine miRNAs was further validated by real-time RT-PCR in an independent set of malignant astrocytomas (n=72) and normal samples (n=7). Inhibition of two glioblastoma-upregulatedmiRNAs (miR-21 and miR-23a) and exogenous overexpression of two glioblastoma-downregulatedmiRNAs (miR-218 and miR-219-5p) resulted in reduced soft agar colony formation but showed varying effects on cell proliferation and chemosensitivity. Thus, we have identified the grade specific expression of miRNAs in malignant astrocytoma and identified a miRNA expression signature to classify grade III astrocytoma from grade IV glioblastoma. In addition, we have demonstrated the functional relevance of miRNA modulation and thus showed the miRNA involvement and their importance in astrocytoma development.
Part B. miR-219-5p inhibits the receptor tyrosine kinase pathway by targeting mitogenic receptor kinases in glioblastoma
The receptor tyrosine kinase (RTK) pathway, being one of the important growth promoting pathways, is known to be deregulated in 88% of the patients with glioblastoma. In order to understand the role of miRNAs in regulating the RTK pathway, we undertook a screening procedure to identify the potential miRNAs that could target different members of the RTK pathway. From the screening study involving bioinformatical prediction of miRNAs and subsequent experimental validation by modulation of miRNA levels in glioma cell lines, we identified miR-219-5p as a candidate miRNA. The overexpression of miR-219-5p reduced the protein levels of both EGFR and PDGFRα. We confirmed the binding of miR-219-5p to the 3’ UTRs by using reporter plasmids. We also confirmed the specificity of miR-219-5p binding sites in the 3’ UTR of EGFR by site directed mutagenesis of binding sites which abrogated the miRNA-UTR interaction. The expression of miR-219-5p was significantly downregulated in grade III as well as in grade IV astrocytoma samples in the miRNA microarray experiment and we further validated the downregulation in an independent cohort of grade III and grade IV astrocytoma patients by real-time qRT-PCR. The ectopic overexpression of miR-219-5p in glioma cell lines inhibited cell proliferation, colony formation, anchorage independent growth and the migration of glioma cells. In addition, overexpression of miR-219-5p decreased MAPK and PI3K pathways, in concordance with its ability to target EGFR and PDGFRα. Additionally, for the further characterization of miR-219-5p – EGFR interaction and its effect on MAPK and PI3K pathways, we used U87 glioma cells that stably overexpress wild-type EGFR and constitutively active ΔEGFR (both lacking 3’-UTR and thus being insensitive to miR-219-5p overexpression) along with U87 parental cells. In these cell lines with the overexpression of EGFR lacking 3’-UTR, miR-219-5p was unable to inhibit - MAPK and PI3K pathways and also glioma cell migration suggesting that these effects were indeed because of its ability to target EGFR. Further, in the glioblastoma patient cohort (TCGA dataset), we found significant negative correlation between EGFR protein levels, both total EGFR and phospho EGFR and miR-219-5p levels in the glioblastoma tissue samples suggesting a role of miR-219-5p in increasing the protein levels of EGFR in glioblastoma. In summary, we have identified and characterized miR-219-5p as the RTK regulating tumor suppressor miRNA in glioblastoma.
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Tissue-specific gain of wild-type RTK levels combined with screen strategies identify new mechanisms of cell vulnerability in developmental and tumorigenic programsFan, Yannan 18 November 2016 (has links)
Pour étudier la capacité cellulaire à s’adapter aux changements de signalisation dépendante des RTKs, nous utilisons un modèle de souris où l’expression du RTK Met sauvage peut être accrue dans un tissu spécifique. La plupart des tissus se protègent contre cette expression anormale des RTK. Mais certains types cellulaires sont sensibles aux altérations des RTKs, c’est le cas du mésenchyme du membre pendant l’embryogenèse. En effet, l’expression de certains gènes du mésenchyme est modifiée et celui-ci n’est plus accessible aux myoblastes qui le colonisent, conduisant à des déficits des muscles du membre. Chez l’adulte une augmentation de l’expression de Met dans le foie (Alb-R26Met) perturbe l’homéostasie tissulaire, conduisant à la tumorigenèse. Pour identifier des gènes qui coopèrent avec les RTKs pendant l’initiation de la tumorigenèse, nous avons combiné les souris Alb-R26Met avec le système de mutagenèse Sleeping Beauty (SB) transposon. 285 gènes putatifs liés au cancer ont été identifiés. Certains sont des proto-oncogènes ou suppresseurs de tumeurs déjà connus, validant le système. D’autres gènes n’avaient, jusqu’à présent, jamais été associés à ce processus. 9 candidats ont été fonctionnellement validés. Pour identifier des signaux assurant le maintien de la tumeur, nous avons analysé le phosphokinome, testé l’efficacité de composés et identifié de nouvelles combinaisons de drogues qui agissent en synergie pour tuer les cellules cancéreuses dérivées de Alb-R26Met. En conclusion, ces travaux montrent qu’une approche génétique non-biaisée combinée à une approche génomique permet d’identifier de nouveaux mécanismes pertinents pour la biologie du cancer. / We explore the cell competence to deal with slight changes in RTK inputs during embryogenesis and tissue homeostasis using a mouse model in which wild-type RTK Met levels can be moderately enhanced in a tissue specific manner. Most tissues buffer enhanced RTK levels thus avoiding perturbation of developmental programs and tissue homeostasis. Nevertheless, certain cell types are vulnerable to RTK levels. During embryogenesis, the limb mesenchyme is sensitive to alterations of the spatial distribution of RTKs, as illustrated by gene expression changes and by loss of accessibility to incoming myoblasts, which lead to limb muscle defects. At adulthood, liver enhanced Met levels (Alb-R26Met) perturbs tissue homeostasis, leading to tumorigenesis. To uncover new genes that cooperate with RTKs during tumour initiation, we combined Alb-R26Met mice with the Sleeping Beauty (SB) transposon mutagenesis system. 285 putative cancer-related genes have been identified. Some correspond to known proto-oncogenes or tumour suppressors, thus validating the overall strategy we employed for cancer gene discovery. Others have not been previously linked to cancer. 9 new tumour suppressors have been functionally validated, demonstrating the validity of our screen strategy. To identify signals involved in tumour maintenance, we employed a phosphokinome-guided drug screen and identified new synergistic drugs deleterious for cancer cells modelled by the Alb-R26Met genetic setting. The overall strategy and outcomes strengthen the value of combining unbiased genetic and genomic approaches to identify new mechanisms relevant for cancer biology and new therapeutic interventions.
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Geodetické činnosti při rekonstrukci vozovky v ulici Otakara Ševčíka / Geodetic activities in reconstruction of the road in Otakara Ševčíka streetSuchánková, Tereza January 2020 (has links)
The subject of this diploma thesis is a description of complex surveying activities during the reconstruction of the road in Otakara Ševčíka Street in cadastral area Židenice. This work describes connection of the points to the coordinate system S-JTSK and to the height system Bpv. Geodetic documentation is made for individual measurements and laying out. Next is the analysis of measurement accuracy and comparison of achieved values with deviations specified in the relevant ČSN.
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Autonomní robotické měření záření gama / Autonomous Robotic Gamma Radiation MeasurementLázna, Tomáš January 2017 (has links)
Tato práce se zaměřuje na autonomní lokalizaci radiologických zdrojů v definované oblasti zájmu. Jejím cílem je vyvinout lokalizační strategie a platformu, na které je bude možné vyzkoušet. Platforma je sestavena z průzkumného robotu Orpheus-X3, scintilačních detektorů a přesného GNSS přijímače. Algoritmus pro vytváření mapy distribuce radiačního pole je rozšířen. Jsou představeny nové metody založené na směrové citlivosti navrhovaného detekčního systému. Počáteční průzkum oblasti zájmu je uskutečněn pomocí kružnicových trajektorií. Všechny algoritmy byly otestována jak simulacemi, tak reálnými experimenty. Dosažená přesnosti lokalizace je v řádu desítek centimetrů. Časová efektivita je použitím nových algoritmů zvýšena přibližně dvakrát až pětkrát. Jedním z~přínosů práce je vývoj modulárního systému, který může být přesunut a uzpůsoben na jiné platformy. Výhodou použitého systému je vysoký stupeň autonomie a bezpečnost pro lidského operátora.
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Raios de curvatura, larguras de bitola e comprimentos do cabeçalho influenciam na qualidade do paralelismo? /Nicolau, Francisca Edcarla de Araujo January 2020 (has links)
Orientador: Carlos Eduardo Angeli Furlani / Resumo: As propriedades que atuam no deslizamento lateral de um equipamento de arrasto em áreas agrícolas, variam amplamente, indo desde as relacionadas ao solo até aos parâmetros envolvidos no sistema trator-equipamento que podem afetar o deslocamento lateral. O objetivo com o estudo foi mensurar o erro de paralelismo do conjunto trator-protótipo em função de diferentes raios de curvatura, larguras de bitola e comprimentos do cabeçalho de um protótipo de arrasto, além de avaliar a variabilidade do processo por meio do Controle Estatístico do Processo. Os testes foram realizados em área experimental da Universidade Estadual Paulista (Unesp), Faculdade de Ciências Agrárias e Veterinárias, Câmpus de Jaboticabal. Foi adaptado o chassi de uma semeadora-adubadora, que possibilitasse mudança no comprimento do cabeçalho e variação na largura da bitola do equipamento, o qual denominamos protótipo de arrasto. O delineamento experimental foi o inteiramente casualizado, em esquema fatorial 5x4x15, com cinco comprimentos do cabeçalho e quatro larguras de bitola do protótipo em quinze raios de curvatura médio. A medição do paralelismo entre as passadas do conjunto trator-protótipo foi obtida por meio de um instrumento desenvolvido que denominamos “pirulito” e com o auxílio de uma trena. Nos raios de 16,4 m e de 20 m os erros de paralelismo são maiores, em todas as bitolas e vão diminuindo à medida que se aumenta a circunferência do raio. O comprimento do cabeçalho de 2,40 m, quando comparado com ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The properties that act on the lateral sliding of a trailed equipment in agricultural areas, change widely, ranging from those related to the soil to the parameters involved in the tractor-equipment system that can affect lateral displacement. The objective of the study was to measure the parallelism error of the tractor-prototype set as a function of different curvature radius, the widths of the gauge and the lengths of the header of a drag prototype, in addition, the evaluating process of the variability through the Statistical Process Control. The tests were carried out in an experimental area at the São Paulo State University (Unesp), School of Agricultural and Veterinary Sciences, Campus of Jaboticabal. The chassis of a seeder-fertilizer was adopted, so that it would allow a change in the length of the header and a variation in the width of the gauge of the equipment, which we call the trailed prototype. The experimental design was entirely randomized, in a 5x4x15 factorial scheme, with five header lengths and four widths of gauge of the prototype in fifteen average curvature radius. The measurement of the parallelism between the steps of the tractor-prototype set was obtained by using an instrument that we call “lollipop” and with the help of a measuring tape. In the 16.4 m and 20 m radius the parallelism errors were greater than the other gauges, and it decreased as the radius circumference increased. The header length of 2.40 m, when compared to the others, obtained t... (Complete abstract click electronic access below) / Doutor
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Combination of Th1 cytokines plus small molecule kinase inhibitors Palbociclib or Sunitinib potentiate apoptosis in breast cancer cell linesGhimirey, Nirmala 26 July 2018 (has links)
No description available.
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VBS-RTK GPS輔助UAV影像自率光束法空三平差之研究 / VBS-RTK GPS Supported Self-Calibration Bundle Adjustment for Aerial Triangulation of Unmanned Aerial Vehicle Images李敏瑜, Li, Min Yu Unknown Date (has links)
無人飛行載具(Unmanned Aerial Vehicle, UAV)於要求精度之圖資測製應用時,因飛行高度較低並可在雲下飛行取像,與大型載具相比可更機動性獲取空間解析度較高之影像,雖無法如大型載具酬載大像幅感測器供大區域圖資製作,但於小區域之圖資更新卻相當適合。但一般UAV因酬載重量限制,僅可酬載體積小且重量輕之感測器,如非量測型相機及低精度定位定向系統,即AHRS系統。因此,本研究嘗試在UAV上酬載Trimble BD970 GNSS OEM GPS接收模組,此GPS接收模組體積小且重量輕可安置於UAV上,並透過VBS-RTK GPS定位技術獲取UAV精確飛行軌跡資訊,再經時間內插相機曝光瞬時的GPS資訊供空中控制使用,輔助UAV影像空中三角測量(簡稱空三)平差,以降低地面控制點需求。
但欲引入GPS觀測量供空中控制使用必須考量GPS天線與相機投影中心偏移量之問題,但因UAV所酬載之非量測型相機,將造成此偏移量不易透過地面測量方式測得,於本研究將於空三平差時使用線性漂移參數克服此偏移量無法量測之問題;此外,UAV所酬載之非量測型相機,相機參數乃透過地面近景攝影測量以自率光束法平差方式率定所得,但率定所得相機參數無法完全描述相機在航拍取像時的情況,故本研究於空三平差將採用自率光束法克服相機參數率定不完全之問題。實驗中,首先確定GPS模組BD970在VBS-RTK GPS定位技術下在地面高速移動時可獲得高精度的定位成果;接續驗證線性漂移參數及自率光束法平差於此研究的適用性;最後亦探討不同地面控制點配置及來源對空三平差之精度探討,並提出1/5000基本圖圖資測製精度要求下,VBS-RTK GPS輔助UAV影像自率光束法空三平差的地面控制點最適配置。 / UAV(Unmanned Aerial Vehicle) is currently used in civil purpose such as mapping and disaster monitoring. One of UAV advantages is to collect images with high resolution for mapping demand. However, due to payload limitations of UAV, it is difficult to mount metric aerial camera and precise POS(Positioning and Orientation System) device. Instead, only the non-metric camera and the low accurate AHRS (Attitude and Heading Reference System) can be installed. For mapping demands, Trimble BD970 GNSS OEM board will be carried on the UAV to collect the high accurate flying trajectory as control information for AT (aerial triangulation) by VBS-RTK(Virtual Base Station - Real Time Kinematic) GPS technique. Meanwhile self-calibration bundle adjustment will be employed for AT(Aerial Triangulation) to overcome the imperfect calibration of non-metric camera by the close-range photogrammetric approach. The precise offset between image perspective center and GPS antenna center, called GPS antenna-camera offset, is hard to measure in centimenter level by terrestrial measurement approach. Therefore the drift parameters will be utilized to solve the problem of GPS antenna-camera offset while performing bundle adjustment with self-calibration for AT of UAV images. In the experiments of this study, the height positioning accuracy of BD970 by VBS-RTK GPS approach at high speed movement will be proved firstly. Then the adaptability of drift parameters and self-calibration for GPS supported AT of UAV images will be verified. Finally, the accuracy of AT by using different control information will be analized and appropriate configuration of GCPs(Ground Control Points) for VBS-RTK GPS supported self-calibration bundle adjustment for AT of UAV images will be proposed under the mapping demand with the scale of 1 : 5000.
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Oceanographic Considerations for the Management and Protection of Surfing BreaksScarfe, Bradley Edward January 2008 (has links)
Although the physical characteristics of surfing breaks are well described in the literature, there is little specific research on surfing and coastal management. Such research is required because coastal engineering has had significant impacts to surfing breaks, both positive and negative. Strategic planning and environmental impact assessment methods, a central tenet of integrated coastal zone management (ICZM), are recommended by this thesis to maximise surfing amenities. The research reported here identifies key oceanographic considerations required for ICZM around surfing breaks including: surfing wave parameters; surfing break components; relationship between surfer skill, surfing manoeuvre type and wave parameters; wind effects on waves; currents; geomorphic surfing break categorisation; beach-state and morphology; and offshore wave transformations. Key coastal activities that can have impacts to surfing breaks are identified. Environmental data types to consider during coastal studies around surfing breaks are presented and geographic information systems (GIS) are used to manage and interpret such information. To monitor surfing breaks, a shallow water multibeam echo sounding system was utilised and a RTK GPS water level correction and hydrographic GIS methodology developed. Including surfing in coastal management requires coastal engineering solutions that incorporate surfing. As an example, the efficacy of the artificial surfing reef (ASR) at Mount Maunganui, New Zealand, was evaluated. GIS, multibeam echo soundings, oceanographic measurements, photography, and wave modelling were all applied to monitor sea floor morphology around the reef. Results showed that the beach-state has more cellular circulation since the reef was installed, and a groin effect on the offshore bar was caused by the structure within the monitoring period, trapping sediment updrift and eroding sediment downdrift. No identifiable shoreline salient was observed. Landward of the reef, a scour hole ~3 times the surface area of the reef has formed. The current literature on ASRs has primarily focused on reef shape and its role in creating surfing waves. However, this study suggests that impacts to the offshore bar, beach-state, scour hole and surf zone hydrodynamics should all be included in future surfing reef designs. More real world reef studies, including ongoing monitoring of existing surfing reefs are required to validate theoretical concepts in the published literature.
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