Proceedings of the Second Airborne Imaging Spectrometer Data Analysis Workshop

Topics addressed include: calibration, the atmosphere, data problems and techniques, geological research, and botanical and geobotanical research

An Intelligent Multi-Resolutional and Rotational Invariant Texture Descriptor for Image Retrieval Systems

To find out the identical or comparable images from the large rotated databases with higher retrieval accuracy and lesser time is the challenging task in Content based Image Retrieval systems (CBIR). Considering this problem, an intelligent and efficient technique is proposed for texture based images. In this method, firstly a new joint feature vector is created which inherits the properties of Local binary pattern (LBP) which has steadiness regarding changes in illumination and rotation and discrete wavelet transform (DWT) which is multi-resolutional and multi-oriented along with higher directionality. Secondly, after the creation of hybrid feature vector, to increase the accuracy of the system, classifiers are employed on the combination of LBP and DWT. The performance of two machine learning classifiers is proposed here which are Support Vector Machine (SVM) and Extreme learning machine (ELM). Both proposed methods P1 (LBP+DWT+SVM) and P2 (LBP+DWT+ELM) are tested on rotated Brodatz dataset consisting of 1456 texture images and MIT VisTex dataset of 640 images. In both experiments the results of both the proposed methods are much better than simple combination of DWT +LBP and much other state of art methods in terms of precision and accuracy when different number of images is retrieved.  But the results obtained by ELM algorithm shows some more improvement than SVM. Such as when top 25 images are retrieved then in case of Brodatz database the precision is up to 94% and for MIT VisTex database its value is up to 96% with ELM classifier which is very much superior to other existing texture retrieval methods

Dendritic integration in olfactory bulb granule cells: Thresholds for lateral inhibition and role of active conductances upon 3D multi-site photostimulation of spines using a holographic projector module

The inhibitory axonless olfactory bulb granule cells (OB GCs) form reciprocal dendrodendritic synapses with mitral and tufted cells (MCs and TCs) via large spines, mediating recurrent and lateral inhibition. Rat GC dendrites are excitable by local Na⁺ spine spikes and global Ca²⁺- and Na⁺-spikes. Since reaching global threshold potentials also represents the onset of lateral inhibition, the goal of my work was to investigate the exact transition from local to global signalling: How many spines, in which position and distribution on the dendritic tree have to be activated to trigger global spikes and what are the molecular key players, i.e. which ion channels are involved. In the first part of this study we have integrated a holographic projector into the existing commercial two-photon (2P) Galvanometer-based 2D laser scanning microscope with an uncaging unit (Uncaging: Activation of photolabile biologically inactive derivatives of neurotransmitters by photolysis), which allows the simultaneous photostimulation of several spines in three dimensions (3D) in acute brain slices. Patterned 2P photolysis via holographic illumination is a powerful method to investigate neuronal function because of its capability to emulate multiple synaptic inputs in three dimensions (3D) simultaneously. However, like any optical system, holographic projectors have a finite space-bandwidth product that restricts the spatial range of patterned illumination or field-of-view (FOV) for a desired resolution. Such trade-off between holographic FOV and resolution restricts the coverage within a limited domain of the neuron’s dendritic tree to perform highly resolved patterned 2P photolysis on individual spines. Here, we integrate a holographic projector into a commercial 2P galvanometer-based 2D scanning microscope with an uncaging unit and extend the accessible holographic FOV by using the galvanometer scanning mirrors to reposition the holographic FOV arbitrarily across the imaging FOV. The projector system utilizes the microscope’s built-in imaging functions. Stimulation positions can be selected from within an acquired 3D image stack (the volume of interest, VOI) and the holographic projector then generates 3D illumination patterns with multiple uncaging foci. The imaging FOV of our system is 800×800 μm² within which a holographic VOI of 70×70×70 μm³ can be chosen at arbitrary positions and also moved during experiments without moving the sample. We describe the design and alignment protocol as well as the custom software plugin that controls the 3D positioning of stimulation sites. We demonstrate the neurobiological application of the system by simultaneously uncaging glutamate at multiple spines within dendritic domains and consequently observing summation of postsynaptic potentials at the soma, eventually resulting in APs. At the same time, it is possible to perform 2P Ca²⁺ imaging in 2D in the dendrite and thus to monitor synaptic Ca²⁺ entry in selected spines and also local regenerative events such as dendritic APs. In the second part of this study we applied the system to study dendritic integration in GCs. Less than 10 coactive reciprocal spines were sufficient to generate diverse regional and global signals that also included local dendritic Ca²⁺- and Na⁺-spikes (D-spikes). Individual spines could sense the respective signal transitions as increments in Ca²⁺ entry. Dendritic integration was mostly linear until a few spines below global Na⁺-spike threshold, where often D-spikes set in. NMDARs strongly contributed to active integration, whereas morphological parameters barely mattered. In summary, thresholds for GC-mediated bulbar lateral inhibition are low

Modelling the human perception of shape-from-shading

Shading conveys information on 3-D shape and the process of recovering this information is called shape-from-shading (SFS). This thesis divides the process of human SFS into two functional sub-units (luminance disambiguation and shape computation) and studies them individually. Based on results of a series of psychophysical experiments it is proposed that the interaction between first- and second-order channels plays an important role in disambiguating luminance. Based on this idea, two versions of a biologically plausible model are developed to explain the human performances observed here and elsewhere. An algorithm sharing the same idea is also developed as a solution to the problem of intrinsic image decomposition in the field of image processing. With regard to the shape computation unit, a link between luminance variations and estimated surface norms is identified by testing participants on simple gratings with several different luminance profiles. This methodology is unconventional but can be justified in the light of past studies of human SFS. Finally a computational algorithm for SFS containing two distinct operating modes is proposed. This algorithm is broadly consistent with the known psychophysics on human SFS

Application of remote sensing to selected problems within the state of California

There are no author-identified significant results in this report

Dust Devil Populations and Statistics

The highly-skewed diameter and pressure drop distributions of dust devils on Earth and Mars are noted, and challenges of presenting and comparing different types of observations are discussed. The widely- held view that Martian dust devils are larger than Earth\u27s is critically-assessed: the question is confounded somewhat by different observation techniques, but some indication of a ~3x larger population on Mars is determined. The largest and most intense (in a relative pressure sense) devils recorded are on Mars, although the largest reported number density is on Earth. The difficulties of concepts used in the literature of \u27average\u27 diameter, pressure cross section, and area fraction are noted in the context of estimating population-integral effects such as dust lifting

Geologic and mineral and water resources investigations in western Colorado, using Skylab EREP data

The author has identified the following significant results. Skylab photographs are superior to ERTS images for photogeologic interpretation, primarily because of improved resolution. Lithologic contacts can be detected consistently better on Skylab S190A photos than on ERTS images. Color photos are best; red and green band photos are somewhat better than color-infrared photos; infrared band photos are worst. All major geologic structures can be recognized on Skylab imagery. Large folds, even those with very gentle flexures, can be mapped accurately and with confidence. Bedding attitudes of only a few degrees are recognized; vertical exaggeration factor is about 2.5X. Mineral deposits in central Colorado may be indicated on Skylab photos by lineaments and color anomalies, but positive identification of these features is not possible. S190A stereo color photography is adequate for defining drainage divides that in turn define the boundaries and distribution of ground water recharge and discharge areas within a basin

Bubble characteristics from breaking waves in fresh water and simulated seawater

The appearance of bubbles was determined in three different wind wave facilities utilizing an optical bright field technique. Based on the bubble detection algorithm by W. Mischler [20], an algorithm has been developed by means of which bubbles and their sizes can be detected automatically. The method is applicable up to moderate to high bubble densities. At the Aeolotron bubble detection up to the water surface is feasible. It has been shown that the density of bubbles correlates to wind speed, water conditions, the distance to the water surface as well as to the tank geometry. Observations show an increased bubble density in salt water compared to fresh water at the same wind conditions. A study on the influence of lower Butanol concentrations of about 50ml/m^3 was carried out. Low Butanol concentrations in the water lead to an increased density of bubbles and additionally, as could be shown in the Aeolotron, a significant increase of very small bubbles (r<65µm). Adding Butanol seems to be a good, non-corrosive substitute for seawater. The influence of the fetch length was systematically researched by carrying out measurement series in the annular wind wave facility in Heidelberg as well as measurement series in linear wind wave facilities in Marseille, France and Kyoto Japan, both of which have different sizes and fetch lengths. Comparing these three wind wave facilities a high correlation between the appearance of bubbles and the fetch length could be detected. Analysis of fresh water measurements at hurricane like wind conditions lead to the discovery of a saturation effect on the appearance of bubbles