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Birka är ingen ö : om båtgravar, barockspännen och laserskanningNeiß (Neiss), Michael January 2012 (has links)
När vikingatiden kommer på tal, leds tankarna ofta osökt till Birka. För även om Birka låg på en ö i Mälaren, så var det allt annat än isolerat. Istället ingick Birka i ett komplext nätverk som täckte såväl nära bygder som fjärran stränder. Därav följer att nyckeln till vår förståelse av Mälardalens vikingatid ofta finns i Birka. Men även det motsatta gäller, och ibland behöver arkeologer titta åt andra håll för att uppnå en bättre förståelse av Birka. Detta ömsesidiga förhållande ska illustreras med hjälp av ett båtgravsfynd från Turinge i Södermanland. / <p>Övriga forskningsfinansiärer:</p><p>Berit Wallenbergs stiftelse ("Transformationer inom vikingatidens djurornamentik"), Helge Ax:son Jonsons stiftelse ("3D-laserskanning som verktyg vid vikingatidsstudier")</p> / En förlorad värld? - Turinge re-visited / 3D-laserskanning som verktyg vid vikingatidsstudier / Transformationer inom vikingatidens djurornamentik
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The role of 3D printing in biological anthropologyAllard, Travis T. 14 September 2006 (has links)
The following work explores the role of 3D printing in biological anthropology. A case study approach is used to provide an understanding of two different applications for 3D printing and to identify a potential methodology for creating 3D models. Case study one looks at the application of 3D printing to reconstruction projects using a flowerpot to test the reconstruction methodology. The second case study uses both laser surface and CT scanning to create a replica of a human skeleton. The two methods of data acquisition are evaluated for advantages and limitations in creating the virtual model. This work shows that there is a role for 3D printing in biological anthropology, but that data acquisition and processing issues are the most significant limiting factors in producing skeletal replicas. / October 2006
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應用全波形空載雷射掃描資料於山區地物分類 / Land cover Classification in Mountain Area Using Full-waveform Airborne Laser Scanned Data湯舜閔, Tang, Shun Min Unknown Date (has links)
空載雷射掃描為一可快速獲取地面物體三維空間資訊之技術,而新型發展之全波形(Full-Waveform)系統可完整記錄雷射回波訊號之波形,透過波形偵測與波形擬合等資料前處理,可得到代表地物獨特反射特性的波形參數資料,包括振幅值(Amplitude)、波形寬(Pulse-width)與後續計算之散射截面積係數(Backscatter cross-section coefficient)。
得到各點位之波形資料後,將以波形資料為主進行位於山區之實驗區地物分類,並將使用由實驗區航照影像提供之RGB波段光譜資料計算之綠度指數(Greenness)與計算影像灰階統計值之紋理參數如均質度(Homogeneity)、熵值(Entropy)與R波段平均值(Mean)等參數輔助分類。分類進行之前,透過抽樣實驗區候選地類包括樹林、草地、道路與樹種建物,並以貝氏定理(Bayes Theorem)分析計算不同地物類別在各分類參數區間內的貝氏機率,接著以多項式函數擬合各地類在不同參數之貝氏機率曲線,並以計算反曲點之方式自動化決定該分類參數之門檻值區間。
分類成果顯示,全波形系統提供之波形資料對於受上層植物遮蔽與陰影區之植物點與道路點之分類有顯著之成果,且透過物體對於波形資料之反射特性不同,具備應用於區別不同建築材質類別之潛力。 / Airborne Laser Scanning is a technique capable of acquiring 3D information of land objects. The latest full-waveform system is further improved with the ability of recording complete waveform of reflected laser signal. After the preprocessing procedures such as pulse detection and pulse fitting, the waveform information including amplitude, pulse width and backscatter cross-section were derived. Such information was valuable as they represented unique properties of land objects.
In this study, waveform information of all scanned points were utilized to classify land cover in the test area located in mountain area. Additionally, the Greenness value as well as the texture parameters such as Homogeneity, Entropy and Mean of R band calculated from the ortho-image were used for classification. We aimed to classify the point cloud into vegetation, road and building categories. The Bayes Theorem was used to determine the threshold range of each parameters for classification. As a result, the waveform information were useful for classifying road points covered by upper vegetation points and also vegetation and road points located in shadow area. Moreover, through the analysis of reflective properties of different object using waveform parameters, it was of potential to be applied to distinguish material of buildings.
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Automated Recognition of 3D CAD Model Objects in Dense Laser Range Point CloudsBosche, Frederic January 2008 (has links)
There is shift in the Architectural / Engineering / Construction and Facility Management (AEC&FM) industry toward performance-driven projects. Assuring
good performance requires efficient and reliable performance control processes.
However, the current state of the AEC&FM industry is that control processes are
inefficient because they generally rely on manually intensive, inefficient, and often
inaccurate data collection techniques.
Critical performance control processes include progress tracking and dimensional
quality control. These particularly rely on the accurate and efficient collection
of the as-built three-dimensional (3D) status of project objects. However, currently available
techniques for as-built 3D data collection are extremely inefficient, and provide
partial and often inaccurate information. These limitations have a negative impact
on the quality of decisions made by project managers and consequently on project
success.
This thesis presents an innovative approach for Automated 3D Data Collection
(A3dDC). This approach takes advantage of Laser Detection and Ranging
(LADAR), 3D Computer-Aided-Design (CAD) modeling and registration technologies.
The performance of this approach is investigated with a first set of experimental
results obtained with real-life data. A second set of experiments then
analyzes the feasibility of implementing, based on the developed approach, automated
project performance control (APPC) applications such as automated project
progress tracking and automated dimensional quality control. Finally, other applications
are identified including planning for scanning and strategic scanning.
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Automated Recognition of 3D CAD Model Objects in Dense Laser Range Point CloudsBosche, Frederic January 2008 (has links)
There is shift in the Architectural / Engineering / Construction and Facility Management (AEC&FM) industry toward performance-driven projects. Assuring
good performance requires efficient and reliable performance control processes.
However, the current state of the AEC&FM industry is that control processes are
inefficient because they generally rely on manually intensive, inefficient, and often
inaccurate data collection techniques.
Critical performance control processes include progress tracking and dimensional
quality control. These particularly rely on the accurate and efficient collection
of the as-built three-dimensional (3D) status of project objects. However, currently available
techniques for as-built 3D data collection are extremely inefficient, and provide
partial and often inaccurate information. These limitations have a negative impact
on the quality of decisions made by project managers and consequently on project
success.
This thesis presents an innovative approach for Automated 3D Data Collection
(A3dDC). This approach takes advantage of Laser Detection and Ranging
(LADAR), 3D Computer-Aided-Design (CAD) modeling and registration technologies.
The performance of this approach is investigated with a first set of experimental
results obtained with real-life data. A second set of experiments then
analyzes the feasibility of implementing, based on the developed approach, automated
project performance control (APPC) applications such as automated project
progress tracking and automated dimensional quality control. Finally, other applications
are identified including planning for scanning and strategic scanning.
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Miniature laser scanning micro-endoscopes : multi-modality imaging system and biomedical applicationsWang, Youmin, 1986- 15 July 2013 (has links)
Cancer is a world menace. After years of endeavor seeking the end of it, people started to realize that no matter how powerful the therapy could be, detection at early stage is always a cheaper, easier and more successful solution compared with curative methods for cancer developed onto its advanced stage. However, relatively few early-detection approaches have proven sufficiently effective and practical for mass use as a point-of-care tool. An early-cancer screening tool integrating the desired features of sensitive, informative, portable, and cost-effective is in need for the doctors.
The progress in optical imaging and Micro-electro-mechanical system (MEMS) technology offers a promise for an innovative cancer screening alternative that is non-invasive, radiation-free, portable and potentially cost-effective. This dissertation investigates handheld instrumentation as multi-modalities of miniature imaging probes with various designs of MEMS devices, to obtain real-time images of epithelial tissue optical and physiological properties, combining the quantitative advantages of spectral analysis with the qualitative benefits of imaging to distinguish early cancer. This dissertation in sequence presents the handheld instruments in the fashions of Laser-scanning confocal microscopy (LSCM), optical diffuse reflectance imaging, nonlinear optical imaging modalities with their subsequent image-guided managements in oral cancer, skin cancer detection, circulating tumor cell (CTC) imaging, and imaging guided surgeries.
One of the main challenges facing miniaturization lies in the mechanism of beam deflection across the sample. This dissertation introduces two generations of MEMS devices desgined, fabricated and incorporated in the imaging probes. A two-axis vertical comb driven silicon micromirror was used in the development of a handheld LSCM for oral cancer detection. Though obtaining numerous advantages, this first generation silicon MEMS micromirror suffers from small aperture size and high voltage requirement for actuation, which result in low collection efficiency in fluorescence imaging and medial safety concerns, respectively. Therefore a stainless steel scanner compatible with electrical discharge machining (EDM) process was fabricated with simplified process, low-voltage magnetic actuation and large fluorescence collection efficiency, with its capability demonstrated in the incorporation and embodiment of a handheld hyperspectral nonlinear imaging probe.
Besides, software and controlling innovations for handheld imaging modalities are presented. A feedback controlling system for MEMS scanning status monitoring was developed for stabilized imaging rendering. For the sake of further improved imaging stability in handheld imaging and to enable on-site mosaic for large field viewing, a handheld mosaic system was developed and presented. / text
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Structural Investigation of Biological and Semiconductor Nanostructures with Nonlinear Multicontrast MicroscopyCisek, Richard 12 December 2013 (has links)
Physical and functional properties of advanced nano-composite materials and biological structures are determined by self-organized atoms and molecules into nanostructures and in turn by microscopic organization of the nanostructures into assemblies of higher structural complexity. Therefore, microscopes are indispensable tools for structural investigations at various levels of organization. In this work, novel nonlinear optical microscopy methods were developed to non-invasively study structural organization at the nanoscopic and microscopic levels. Atomic organization of semiconductor nanowires, molecular organization of amylose biocrystallites in starch granules, and microscopic organization of several photosynthetic organisms was elucidated.
The structure of ZnSe nanowires, key components in many modern nanodevices, was investigated using polarization harmonic generation microscopy. Based on nonlinear optical properties of the different crystal lattices, zinc blende and wurtzite nanowires were differentiated, and the three-dimensional orientation of the zinc blende nanowires could be found. The structure of starch granules, a model biocrystal, important in food as well as health sciences, was also investigated using polarization harmonic microscopy. The study was combined with ab initio calculations using the crystal structures of amylose A and B, revealing that second harmonic signals originate from the hydroxide and hydrogen bonds in the starch granules. Visualization of several photosynthetic organisms including the green algae, Chlamydomonas reinhardtii, two species of cyanobacteria, Leptolyngbya sp. and Anabaena sp., aggregates of light-harvesting pigment-protein complexes as well as chloroplasts from green plants were also explored, revealing that future nonlinear microscopy applications could include structural studies of cell walls, the Chlamydomonas eyespot, and photosynthetic membranes.
In this study, several nonlinear optical microscopy modalities were developed for quantitative structural investigations of nano and micro-sized architectures. Non-invasive extraction of crystallographic information in microscopic samples will have a number of potential benefits, for example, in clinical applications, allowing observations of disease states inside tissues without the need for biopsy. Industrial nanotechnology will benefit from fast determination of nanostructures with nonlinear microscopy that will improve quality of nanodevices.
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Structural Investigation of Biological and Semiconductor Nanostructures with Nonlinear Multicontrast MicroscopyCisek, Richard 12 December 2013 (has links)
Physical and functional properties of advanced nano-composite materials and biological structures are determined by self-organized atoms and molecules into nanostructures and in turn by microscopic organization of the nanostructures into assemblies of higher structural complexity. Therefore, microscopes are indispensable tools for structural investigations at various levels of organization. In this work, novel nonlinear optical microscopy methods were developed to non-invasively study structural organization at the nanoscopic and microscopic levels. Atomic organization of semiconductor nanowires, molecular organization of amylose biocrystallites in starch granules, and microscopic organization of several photosynthetic organisms was elucidated.
The structure of ZnSe nanowires, key components in many modern nanodevices, was investigated using polarization harmonic generation microscopy. Based on nonlinear optical properties of the different crystal lattices, zinc blende and wurtzite nanowires were differentiated, and the three-dimensional orientation of the zinc blende nanowires could be found. The structure of starch granules, a model biocrystal, important in food as well as health sciences, was also investigated using polarization harmonic microscopy. The study was combined with ab initio calculations using the crystal structures of amylose A and B, revealing that second harmonic signals originate from the hydroxide and hydrogen bonds in the starch granules. Visualization of several photosynthetic organisms including the green algae, Chlamydomonas reinhardtii, two species of cyanobacteria, Leptolyngbya sp. and Anabaena sp., aggregates of light-harvesting pigment-protein complexes as well as chloroplasts from green plants were also explored, revealing that future nonlinear microscopy applications could include structural studies of cell walls, the Chlamydomonas eyespot, and photosynthetic membranes.
In this study, several nonlinear optical microscopy modalities were developed for quantitative structural investigations of nano and micro-sized architectures. Non-invasive extraction of crystallographic information in microscopic samples will have a number of potential benefits, for example, in clinical applications, allowing observations of disease states inside tissues without the need for biopsy. Industrial nanotechnology will benefit from fast determination of nanostructures with nonlinear microscopy that will improve quality of nanodevices.
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LiDAR-bildanalys av flutings i södra Norrbotten : Kartering och datering av avvikande isrörelseriktningarVallin, Sara January 2014 (has links)
The aim of this study was to map and date glacial flutings with ice flows deviating from the predominating northwesterly ice flow direction in the southern part of Norrbotten County in northern Sweden, and also to investigate if parts of the glacial landscape are older than previously thought. The traditional view is that most landforms in the area were formed during the late Weichselian (W3). Analysis of the new high resolution elevation model (2 m grid) derived from laser scanning was performed after treating the data with a hillshade tool in ArcMap to reveal terrain features such as flutings. The analysis resulted in a map showing four main groups of deviating ice flows (N-S, NO-SV, SO-NV and S-N) and several westerly ice flows. The majority of flutings with deviating ice flows were found in low terrain. This, together with studies suggesting a cold based late Weichselian ice sheet in Norrbotten, implies an old age of the deviating ice flows. The deviating ice flows are interpreted to originate from the first early Weichselian (W1), or predate the onset of the Weichselian glaciation. Some NV-SO flutings were located in high terrain, which implies a younger age relative to the low terrain flutings. They represent the youngest ice flow found in the area, possibly from the second early Weichselian (W2). The new elevation model clearly offers new possibilities for studying small scale landforms and shows that the traditional view of the Weichselian glaciation in northern Swedish needs to be reconsidered.
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Aspects of amphibian chytrid infections in South Africa / M.C. GerickeGericke, Maria Catharina January 2008 (has links)
The waterborne pathogen Batrachochytrium dendrobatidis (Bd), amphibian chytrid, is
implicated as being the causative agent for global amphibian declines. The fungus attacks the keratinized skin of adult and postmetamorphic animals and the keratinized mouthparts of tadpoles. Postmetamorphic animals seem to be more susceptible to Bd than tadpoles and adult frogs. Hypotheses exist that the origin of the fungus is in Africa. During the study different aspects of Bd infections in South African frogs were examined including the distribution of Bd, cultivation of Bd, preservation of cultures, the morphology of Bd as an infection as well as in culture and finally differences in host defense. Positive and negative localities for Bd were identified through surveys conducted in South Africa. These data will be contributed to the Bd Mapping Project and the African Bd Database in order to determine whether chytrid has any environmental preferences. Cultures obtained from the positive localities were maintained and cryopreserved for use in numerous experiments. In a future study, DNA extractions from the cultures will be analyzed using multilocus sequence typing in order to determine the sequence type of South African strains in comparison with global strains. This will provide important epidemiological information concerning the origin and control of Bd. The morphology of Bd was also examined using scanning electron microscopy and laser scanning confocal microscopy. Damage due to Bd infections was more severe on the larval mouthparts of Amietia vertebralis than that of Hadromophryne natalensis. The adverse effect of Bd is therefore not limited to postmetamorphic animals. Confocal microscopy uses fluorescent stains and lasers to examine specific structures within organisms. An especially effective stain used during confocal microscopy on Bd is Calcofluor White M2R. Due to its specificity this stain can be used as an effective screening tool for Bd in tissue. The role of antimicrobial skin peptides as a defense against Bd was also examined. A. vertebralis experiences die-offs due to chytrid, while H. natalensis does not experience the same effect in the presence of Bd. H. natalensis possess more antimicrobial skin peptides against Bd with a higher effectiveness than peptides extracted from A. vertebralis. This may explain the observed susceptibility of A. vertebralis to Bd. The relevance of this study is in order to identify areas in South Africa in which the probability of finding Bd is high. This will help in the surveillance of Bd and in the identification of susceptible species to be monitored and protected against the fungus. The effect of Bd on frog species can also be determined by means of exposure experiment using cultures isolated during this study. Through the identification of peptides effective against Bd, predictions can be made with regard to the susceptibility of different frogs to Bd, improving our ability to protect the amphibian biodiversity in South Africa. With the use of confocal microscopy in the examination of Bd, we became the first group to use the method. By the identification of a stain with a high potential as a screening tool, we also contributed to the more efficient identification of Bd in tissue. Keywords: Batrachochytrium dendrobatidis, Bd, amphibian chytrid, distribution, cultivation, antimicrobial skin peptides, laser scanning confocal microscopy, Amietia vertebralis, Hadromophryne natalensis, South Africa / Thesis (M. Environmental Science)--North-West University, Potchefstroom Campus, 2009.
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