Airborne Laser Scanning (ALS) point cloud ground filtering for area of an active landslide (Doren, Western Austria)

Ground filtering of point cloud is the primary step required for Digital Terrain Model (DTM) generation. The procedure is especially interesting for forested areas, since LiDAR systems can measure terrain elevation under vegetation cover with a high level of penetration. This work analyzes the potential of ALS data ground filtering for area of an active landslide. The results of ALS filtering, for example, may improve geomorphological and motiondetection studies. ALS data was collected during flight campaign 2011 under leaf-off conditions for Doren region, Vorarlberg, Western Austria. In this area, non-ground objects are mostly low vegetation such as shrubs, small trees etc. The vegetation is more dense in lower part of the landslide where erosion is smaller. Vegetation points can be removed based on the hypothesis that these are significantly higher than their neighboring points. However, in case of steep terrain, ground points may have the same heights as vegetation points, and thus, local slope should be considered. Also, if terrain roughness increases, the classification may become even more complex. Software system OPALS (Orientation and Processing of Airborne Laser Scanning data, Vienna University of Technology) was used for processing the ALS data. Labeling ground points has been made using physical and geometrical attributes (parameters) of ALS points. Also additional attributes were calculated in order to improve extraction. Since bare ground surface is usually smooth and continuous unlike vegetation, standard deviation of local elevations was used as roughness measure to differentiate these surfaces. EchoRatio (ER) was adopted as a measure of surface penetrability, while number of echoes and differentiation between echoes (EchoNumber) were also deployed in filtering. Since the ground points are measurements from bare-earth that are usually the lowest surface features in a local area, normalized height was defined as a rank of neighboring points. Additionally, a so-called openness parameter was used as a convexity/concavity measure of surface. All of the mentioned point attributes have been combined in a decision tree in order to extract bare ground points. Based on a preliminary analysis, it is noted that implemented filtering procedure has difficulties with surfaces with rough terrain or steep relief. There is an assumption for lack of ground points in areas with dense vegetation that reduced the penetration of laser beams to the ground (lower part of a landslide). Also, points representing low vegetation were often labeled as ground points. Procedure produced holes in point cloud which demanded appropriate interpolation methods to be applied.Geophysical Research Abstract

Pouzdanost složenih vodovodnih sistema na primeru RVS Dubovac-Zrenjanin-Kikinda

Water supply networks have a specific feature that makes them more complicated then many other water management systems. Namely, to make sure that the system performs well, apart from the mechanical characteristics of the system, the hydraulic reliability of its components must also be verified. In this particular case the reliability of the regional water supply system Dubovac-Zrenjanin-Kikinda has been assessed, the system being based on the concept of centralized water supply, in which water is conducted from the different regional sources to the municipal centers, and then distributed to the users.Vodovodni (distributivni) sistemi imaju jednu specifičnost koja ih, sa gledišta pouzdanosti, čini složenijim od drugih sistema. Da bi sistem uspešno obavljao svoju funkciju pored pouzdanosti mehaničkih karakteristika sistema uzima se u obzir i pouzdanost hidrauličkih parametara sistema. U ovom radu se na primeru regionalnog vodovodnog sistema Dubovac-Zrenjanin-Kikinda koji se bazira na konceptu centralizovanog vodosnabdevanja dovođenjem vode sa regionalnog izvorišta, preko PPV i dalje regionalnim cevovodima distribuira do opštinskih centara razmatra problem određivanja pouzdanosti vodovodnog sistema

Development and evaluation of 45S5 bioglass scaffolds coated with selenium nanoparticles or with poly(lactide-co-glycolide)/selenium nanoparticles

In the bone tissue engineering field, there is growing interest in the application of bioglass scaffolds due to their bone bonding ability and osteoconductivity. However such scaffolds still lack some of the required functionalities to enable the successful formation of new bone, e.g. enhanced bioactivity by incorporation of bioactive molecules or growth factors and effective antibacterial properties. A large number of epidemiological, preclinical, and clinical trials suggest that selenium (Se) has significant role in antioxidant protection, enhanced immune surveillance and modulation of cell proliferation. Selenium nanoparticles (SeNp) have also been reported to possess antibacterial as well as antiviral activities. Studies also provide evidence that Se intake may be necessary for bone health. Poly(lactide-co-glycolide) (PLGA) micro and nanoparticles are used for the controlled delivery of several classes of medicaments such as growth factors, antibiotics, antimicrobial agents etc. Uniform, stable, amorphous SeNps have been synthesized and additionally encapsulated within spherical PLGA particles (PLGA/SeNps). Bioglass scaffolds have been synthesized by foam replica method and additionally coated by SeNp or by PLGA with encapsulated SeNp. Samples were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS) and transmission electron microscopy (TEM). SeNp, Bioglass®/SeNp and Bioglass®/PLGA/SeNp showed a considerable antibacterial activity against Gram positive bacteria Staphylococcus aureus and Staphylococcus epidermidis, one of the main causative agents of orthopedic infections

Optical Coherence Tomography (OCT) Imaging Technology

This paper presents short review of the OCT technology concepts, including the recently emerging low-cost OCT devices. Technology concept of Fourier-domain OCT, based on spectral interferometry, is presented: spectral-domain OCT (SD-OCT) and swept-source OCT (SS-OCT). Technical properties of the recently developed low-cost OCT solutions are reviewed. Advanced OCT measurements in clinical ophthalmology are discussed, with relevant case studies. Further research directions that consider AI-based methods in OCT imaging is briefly presented.Accepted for publishin

Electrospinning As The Fabrication Technology For The Energy Harvesting Composites

This paper presents the electrospinning technology as used for the fabrication of the energy harvesting composites, including the review of ceramic-based and polymer-based piezoelectric composites and their electrical outputs for the energy harvesting applications. Energy harvesting is a method for obtaining electrical energy from the environment to be used for powering autonomous electronic devices. Current trend of reducing the size of the devices has led to the increasing number of new energy harvesting materials. Basic principles of fiber fabrication via electrospinning were presented, as well as material characterization methods. The special focus was given to the electrical properties of energy harvesting composites with a review of methods for detecting and measuring electrical outputs of these materials. Electrical performance of the electrospun piezoelectric nanogenerators was discussed.SMART-2M, Innovation Capacity Building for Higher Education in Industry 4.0 and Smart Manufacturing, European Institute of Innovation and Technology (EIT), the European Union’s Horizon 2020 research and innovation program under grant agreement 777204 and projects No. 451-03-9/2021-14/200107 and No. 451-03-9/2021-14/200378, Ministry of Education, Science and Technological Development, SerbiaPublishe

The Review of Materials for Energy Harvesting

This paper presents a short review of the piezoelectric materials in energy harvesting. Energy harvesting principle, as the method for obtaining energy from environment has been described. Materials and material combinations for creating an energy harvesting composites are discussed, such as ceramic- and polymer-based composites and their mechanical properties. The list of the mostly used piezoelectric materials is presented and elaborated. Possible applications of the energy harvesting materials are discussed, including nanogenerators, biosensors and biomedical applications.10.13039/100010686-EIT's HEIAccepted for publishin

Vertikalni i gravimetrijski referentni sistemi Evrope

The paper provides an overview of height and gravity reference systems of Europe and a brief description of their implementation. For each system we have given definitions of the system, as well as changes in definitions over time. In paper we have briefly described European Vertical Reference System-EVRS, United European Leveling Network-UELN, European Vertical Reference Network as well as densification action - EUVN_DA. Gravimetric reference systems are described by the Potsdam reference system, through a system IGSN71 (International Gravity Standardization Network 1971), as well as a series of actions aimed at defining a new gravity reference systems of Europe.U radu je dat pregled visinskih i gravimetrijskih referentnih sistema Evrope i kratak opis njihovih realizacija. U opisu svakog sistema date su definicije sistema, kao i promene definicija u vremenu. U pogledu visinskih sistema i mreža dati su kratki opisi EVROPSKOG VERTIKALNOG REFERENTNOG SISTEMA (European Vertical Reference System - EVRS), UJEDINjENE EVROPSKE NIVELMANSKE MREŽE (United European Leveling Network-UELN), EVROPSKE UJEDINjENE VER- TIKALNE MREŽE (European Vertical Reference Network-EUVN) i akcija koje se izvode u cilju njenog progušćavanja (European United Vertical Network - Densification Action - EUVN_DA). Gravimetrijski referentni sistemi opisani su od Potsdamskog referentnog sistema, preko sistema IGSN71 (International Gravity Standardization Network 1971), kao i nizom akcija u cilju definisanja novog referentnog gravimetrijskog sistema Evrope

Vertikalni i gravimetrijski referentni sistemi Evrope

The paper provides an overview of height and gravity reference systems of Europe and a brief description of their implementation. For each system we have given definitions of the system, as well as changes in definitions over time. In paper we have briefly described European Vertical Reference System-EVRS, United European Leveling Network-UELN, European Vertical Reference Network as well as densification action - EUVN_DA. Gravimetric reference systems are described by the Potsdam reference system, through a system IGSN71 (International Gravity Standardization Network 1971), as well as a series of actions aimed at defining a new gravity reference systems of Europe.U radu je dat pregled visinskih i gravimetrijskih referentnih sistema Evrope i kratak opis njihovih realizacija. U opisu svakog sistema date su definicije sistema, kao i promene definicija u vremenu. U pogledu visinskih sistema i mreža dati su kratki opisi EVROPSKOG VERTIKALNOG REFERENTNOG SISTEMA (European Vertical Reference System - EVRS), UJEDINjENE EVROPSKE NIVELMANSKE MREŽE (United European Leveling Network-UELN), EVROPSKE UJEDINjENE VER- TIKALNE MREŽE (European Vertical Reference Network-EUVN) i akcija koje se izvode u cilju njenog progušćavanja (European United Vertical Network - Densification Action - EUVN_DA). Gravimetrijski referentni sistemi opisani su od Potsdamskog referentnog sistema, preko sistema IGSN71 (International Gravity Standardization Network 1971), kao i nizom akcija u cilju definisanja novog referentnog gravimetrijskog sistema Evrope

Binomial coefficients and their visualization

In this paper, the authors present some of the results achieved by mathematicians who belonged to different cultures and lived in different time periods, but were engaged in determining (formula for determining) binomial coefficients. Also, the authors present a geometric interpretation of the binomial coefficients of the binomial expansion , for and present an idea for the visualization of both binomial and polynomial coefficients that they plan to experimentally test in the upcoming period.Publishe

Comparative Study of the Antimicrobial Activity of Selenium Nanoparticles With Different Surface Chemistry and Structure

Although selenium nanoparticles (SeNPs) have gained attention in the scientific community mostly through investigation of their anticancer activity, a great potential of this nanomaterial was recognized recently regarding its antimicrobial activity. The particle form, size, and surface chemistry have been recognized as crucial parameters determining the interaction of nanomaterials with biological entities. Furthermore, considering a narrow boundary between beneficial and toxic effects for selenium per se, it is clear that investigations of biomedical applications of SeNPs are very demanding and must be done with great precautions. The goal of this work is to evaluate the effects of SeNPs surface chemistry and structure on antimicrobial activity against several common bacterial strains, including Staphylococcus aureus (ATCC 6538), Enterococcus faecalis (ATCC 29212), Bacillus subtilis (ATCC 6633), and Kocuria rhizophila (ATCC 9341), as well as Escherichia coli (ATCC 8739), Salmonella Abony (NCTC 6017), Klebsiella pneumoniae (NCIMB 9111) and Pseudomonas aeruginosa (ATCC 9027), and the standard yeast strain Candida albicans (ATCC 10231). Three types of SeNPs were synthesized by chemical reduction approach using different stabilizers and reducing agents: (i) bovine serum albumin (BSA) + ascorbic acid, (ii) chitosan + ascorbic acid, and (iii) with glucose. A thorough physicochemical characterization of the obtained SeNPs was performed to determine the effects of varying synthesis parameters on their morphology, size, structure, and surface chemistry. All SeNPs were amorphous, with spherical morphology and size in the range 70–300 nm. However, the SeNPs obtained under different synthesis conditions, i.e. by using different stabilizers as well as reducing agents, exhibited different antimicrobial activity as well as cytotoxicity which are crucial for their applications. In this paper, the antimicrobial screening of the selected systems is presented, which was determined by the broth microdilution method, and inhibitory influence on the production of monomicrobial and dual-species biofilm was evaluated. The potential mechanism of action of different systems is proposed. Additionally, the cytotoxicity of SeNPs was examined on the MRC-5 cell line, in the same concentration interval as for antimicrobial testing. It was shown that formulation SeNPs-BSA expressed a significantly lower cytotoxic effect than the other two formulations