Investigating submerged morphologies by means of the low-budget “GeoDive” method (high resolution for detailed 3D reconstruction and related measurements)

Geophysical methods allow to collect geological data on lake and sea bottoms and characterize large areas, even at high depths, but with high costs. Moreover, the most widespread acquisition methods for morpho-bathymetric survey and the related instruments used are almost always ship-, ROV- or AUV-based and consequently they require high budgets. It is known that shallow waters can represent a limit for certain vessels and techniques, preventing the acquisition in the shoreface zone. To overcome the limits, i.e. to survey with high accuracy nearshore shallow waters with a low budget, we tested and tuned the “GeoDive” method that allowed us to survey two test sites, featured by the presence of “block fields” (i.e., accumulations of huge blocks and boulders of gravitational origin) under shallow waters. The “GeoDive” method allowed us to map the submerged morphologies and to acquire high-resolution optical images for further photogrammetric processing. The latter was fundamental to obtain 3D high-resolution models, also with conditions of low visibility. An Action Sport Cam with high definition resolution has been used for video acquisition, in addition to the equipment used during scientific diving. By coupling the processing of underwater-acquired data with the direct surveys performed by underwater SCUBA operators, it was possible to perform some morphological and sedimentological measurements and observations on the experimental targets, with the help of suitable markers

Object descriptors based on a list of rectangles: method and algorithm

peer reviewedMost morphological operators use a unique structuring element, possibly at different scales, to describe an object. In addition, morphological algorithms are often restricted to 1D structuring elements, combinations of 1D elements, or isotropic structuring elements (like circles), because of the lack of methods directly applicable to 2D structuring elements. While these descriptors have proved useful in the past, we propose an alternative that uses the list of maximal rectangles contained in a set X. In particular, we focus on an opening that preserves large rectangles contained in a set X and on its companion 2D algorithm that builds a list of all the maximal rectangles that fit inside an arbitrary set X. This list is the base of new descriptors that have been used successfully for machine learning tasks

Granulometric characterization of paleosols in loess series by automated static image analysis

An automated image analysis method is proposed here to study the size and shape of siliciclastic sedimentary particles of paleosols of Central European loess sequences. Several direct and indirect measurement techniques are available for grain size measurements of sedimentary mineral particles. Indirect techniques involve the use of some kind of physical laws, however, all requirements for calculations are in many cases not known. Even so, the direct manual microscopic observation and measurement of large, representative number of grains is time-consuming and sometimes rather subjective. Therefore, automated image analyses techniques provide a new and perspective way to analyse grain size and shape sedimentary particles. Here we test these indirect (laser diffraction) and direct (automated static image analysis) techniques and provide new granulometric (size and shape) data of paleosols. Our results demonstrate that grain size data of the mineral dust samples are strongly dependent on shape parameters of particles, and shape heterogeneity was different between different size classes. Due to the irregular grain shape parameters, uncertainties have arisen also for determination of grain sizes. In this paper we present a possible correction procedure to reduce the differences among the results of the laser diffraction and image analysis methods. By applying new correction factors, results of the two approaches could become closer but the unknown thickness of particles remains a problem to solve. The other presented correction procedure to assess the uncertain 3rd dimension of particles by their intensity-size relationships makes us able to reduce further the deviations of the two sizing methods

Some results on the use of the LANDSAT-1 multispectral images

There are no author-identified significant results in this report

Optimization of the spatial distribution of a therapeutic pressurized aerosol (PIPAC): an ex-vivo study

For a long time, PM has been considered to be a terminal clinical condition. Pressurized intraperitoneal aerosol chemotherapy (PIPAC) is an innovative therapeutic approach with the target to become a curative treatment. The chemotherapeutic drugs are not delivered anymore into the abdominal cavity by conventional lavage, but administered by means of a pressurized, chemotherapeutic drug containing aerosol. The objective is to achieve a homogeneous drug distribution within the abdominal cavity. Through the gaseous propagation of the chemotherapeutic drugs, every region, regardless of its proximity or distance to the nozzle of the nebulizer in the laparoscopic setting, is covered sufficiently. This is not attainable with conventional lavage, where the low abdominal regions are treated sufficiently due to gravitational forces, while the upper regions are less covered, resulting in ineffective cancer treatment, as not all tumor nodules are caught. In the past, various in vivo, ex vivo and postmortem swine experiments have been made to describe and improve the distribution pattern of an injected aerosol and the penetration depth into the serosal tissue. However, theoretical considerations regarding homogenous drug distribution via aerosolized administration did not match with actual results. Drug propagation was found out to be heterogeneous. All presented models suffer from different limitations, such as difficult reproducibility of results, extensive costs, and high discrepancies between anatomical conditions and model setup. Therefore, in this dissertation, a new ex vivo preclinical model, the inverted bovine urinary bladder, has been introduced. Advantages of the inverted bovine urinary bladder include simple handling, cost effectiveness, effect evaluation of various substances both on the mucosa and the serosa, integration of the physico-chemical characteristics of the operational environment, and proximity to the abdominal anatomical conditions. Additionally, so far, no model is able to cover the transient behavior of spray propagation. Therefore, a first dynamic experimental model, the Thermographic Imaging, has been established to describe the aerosol propagation within a model box during the injection period in real time. The presented Thermographic Imaging model is able to characterize the spraying behavior of the inserted different nebulizers and the aerosol propagation behavior during injection phase, but due to technical restrictions is not applicable to the sedimentation process of the aerosol during the exposure period. A further focus of this dissertation is the implementation of a series of experiments, in which aerosols are created via two different nebulizers (Capnopen® and Prototype4) and and their distribution/penetration depth pattern is evaluated in these new established models. First, a visual-qualitative proof of drug distribution in all parts of the bladder was conducted, observing the effect of injected dye methylene blue and ICG. This was enhanced with penetration depth measurements of injected DAPI in three predefined regions within the urinary bladder. Obtained data revealed relevant differences not only between the three different regions, but also between the investigated two Capnopen® types. The Prototype4 achieved superior penetration depth in total and a more homogenous distribution. In a third step, cisplatin, one of the chemotherapeutic drugs used in PIPAC technology, was aerosolized and tissue concentration in the same three locations measured. Obtained data confirm the findings of DAPI penetration depth measurements. These series of experiments show impressively the need of optimizing both the technical, physical, and pharmacodynamic characteristics of the injected aerosol and the distribution pattern. The aerosol characteristics of the Prototype4 are superior in many ways. The combination of improved injection, more homogenous droplet size range, higher and more equally distributed penetration depth values and tissue concentration underlines the achieved aerosol improvement. The inverted bovine urinary bladder turns out to be a valid model for the evaluation of the distribution pattern and penetration depth in the serosal tissue. In the future, these obtained promising results from the preclinical models should be transferred to the clinical operational setting

Offline signature verification using classifier combination of HOG and LBP features

We present an offline signature verification system based on a signature’s local histogram features. The signature is divided into zones using both the Cartesian and polar coordinate systems and two different histogram features are calculated for each zone: histogram of oriented gradients (HOG) and histogram of local binary patterns (LBP). The classification is performed using Support Vector Machines (SVMs), where two different approaches for training are investigated, namely global and user-dependent SVMs. User-dependent SVMs, trained separately for each user, learn to differentiate a user’s signature from others, whereas a single global SVM trained with difference vectors of query and reference signatures’ features of all users, learns how to weight dissimilarities. The global SVM classifier is trained using genuine and forgery signatures of subjects that are excluded from the test set, while userdependent SVMs are separately trained for each subject using genuine and random forgeries. The fusion of all classifiers (global and user-dependent classifiers trained with each feature type), achieves a 15.41% equal error rate in skilled forgery test, in the GPDS-160 signature database without using any skilled forgeries in training