UAV Remote Sensing for delineation of Urban Vegetation using Object Based Image Analysis

Remote sensing technology has rapidly advanced during the last few decades and the number of remote sensing platforms has increased. The development of Unmanned Aerial Vehicles (UAV) image acquisition systems has radically changed the aerial Photogrammetric mapping due to its low cost, high spatial resolution and high accuracy and provide a great potential for vegetation mapping in urban areas. Urban environment planning becomes a challenging task for urban planners due to fast urbanization processes and growth of population. Urban land use is a crucial information for planning authorities and there is a growing demand for urban land cover maps for decision-making procedures in urban planning. In this article, we demonstrate a rule sets knowledge-based classification method, in object oriented classification which is a fully automated and highly accurate engineering approach for demarcation of urban vegetation with the use of eCognition software. DJI Phantom 4, consumer grade drone was used to acquire high resolution aerial photos as an input dataset in the study. In this study, vegetation mapping was done using the textural and contextual information acquired from the RGB image (Orthophoto) without using any Near Infrared (NIR) information and a Digital Surface Model (DSM) which was developed using Pix4D software, used as an ancillary data in the classification process in order to obtain the elevation information. The extraction of tree canopy and the buildings in a coastal urban environment has used to illustrate the analysis. The DSM was validated using ground control points observed by field measurements. The resultant urban vegetation map was validated with the digitized land use layer and an overall accuracy of 90.15% was obtained. This study indicates that low cost drones compared to the survey grade drones, also can provide high accurate and high resolution products suitable for many urban local area planning studies.Keywords: Photogrammetry, Object oriented classification, DSM, Orthophoto, Urban plannin

Poly(m-Phenylenediamine) Nanospheres and Nanorods: Selective Synthesis and Their Application for Multiplex Nucleic Acid Detection

In this paper, we demonstrate for the first time that poly(m-phenylenediamine) (PMPD) nanospheres and nanorods can be selectively synthesized via chemical oxidation polymerization of m-phenylenediamine (MPD) monomers using ammonium persulfate (APS) as an oxidant at room temperature. It suggests that the pH value plays a critical role in controlling the the morphology of the nanostructures and fast polymerization rate favors the anisotropic growth of PMPD under homogeneous nucleation condition. We further demonstrate that such PMPD nanostructures can be used as an effective fluorescent sensing platform for multiplex nucleic acid detection. A detection limit as low as 50 pM and a high selectivity down to single-base mismatch could be achieved. The fluorescence quenching is attributed to photoinduced electron transfer from nitrogen atom in PMPD to excited fluorophore. Most importantly, the successful use of this sensing platform in human blood serum system is also demonstrated

Development of a methodology to map railway lines and surrounding land use using UAVs

High accurate railway maps and terrain information (Digital Elevation Models) is a major concern for future railway constructions and railway lines development.The mapping of railway line using ground based surveying techniques istime consuming and problematic.Unmanned Aerial Vehicles (UAV) technology has revolutionized the aerial photogrammetric mapping due to its low cost and high spatial resolution. It enables mapping the land use with greater accuracy in both 2D and 3D. The “DJI Phantom 4“ drone was selected as the UAV platform to acquire image data. In this study, we have developed a fully automated and highly accurate engineering approach for detecting land use and railway line, which is based on textural information from orthophoto and elevation information (Digital Surface Models)obtained from the drone.The Pix4D software was used to develop the orthophoto and a Digital Surface Model (DSM) and the DSM was validated by using the ground control points.The rule sets knowledge-based classification method in object oriented classification was used to classify the land use and railway with the use of “eCognition“ software. Finally, the results were compared with digitize land use layer to validate the results, and obtained overall accuracy of 90.15%

Nearshore sediment dynamics in Sri Lanka

Coastal environment is a unique morphodynamic system for diverse changes. The present study estimated coastal morphodynamic changes and sediment transportation directions at locations of Uswetakeiyawa beach nourishment and Colombo harbour expansion project areas. In addition, heavy mineral occurrences were studied in beach sediments altogether parameters of mineralogical and geochemical compositions to identify depositional environments. Moreover, time series satellite images were used to identify seasonal coastal sediment accretion and depositional trends. Uswetakeiyawa beach nourishment project area indicates complex sand accretion or erosion, and a net reduction of overall beach widths with reference to the initial field visit. This site records bi-directional sediment transportations by longshore currents during the monsoon periods. Similarly, Colombo harbour expansion project area shows that the cumulative beach erosion has increased after the construction of the breakwater (rate = 0.7 m/year from May 2000 to April 2011 and rate = 28.2 m/year from April 2011 to June 2012). The cumulative and site-specific sand accretion and erosion patterns show clear influence with the monsoon seasonality. Beaches were wider during the stormy south-western monsoon, whereas beaches were narrower during fair weather of north-east monsoon. In contrast, ilmenite, zircon, garnet, monazite and rutile were identified as main heavy minerals in beach sediments. The heavy mineral potential of the north-eastern coast was high (average about 45-50% in the Verugal and 70-85% in the Pulmoddai deposits and 3.5-5.0% in the offshore samples from Nilaveli to Kokkilai), compared to the south-western sediments (average about 10% in onshore and 2% in offshore Gin River mouth). Observed high concentrated heavy minerals in beach and low concentrated offshore sediments suggest the panning system in the surf zone to form enriched placer deposits. The whole rock major and trace compositions of beach sediments were marked enrichment of TiO2, Fe2O3, Ce, Cr, Nb, Th and V compared to the average upper continental crust values. The analysis of prominent coastal longshore transport patterns shows that clockwise flows in the eastern and north-western coasts. In the south-western coast, transport directions were divided into two branches of anti-clockwise and clockwise. Therefore, the schematic representation of monsoon-derived longshore currents suggests that the sources of heavy minerals in the Pulmoddai and Verugal deposits may have probably influenced by clastic sediment supply in eastern India and Sri Lanka (the Mahaweli River), respectively. Heavy minerals in the western coast can probably derive from Precambrian metamorphic rocks, and supplied to coast through river systems in Sri Lanka

Case Report A case of Type 1 hereditary angio-oedema

Hereditary angioedema (HAE) is associated with a deficiency of functionally active C l esterase inhibitor in serum leading to uncontrolled activation of the classical pathway of complement 1 with generation o