Delineation of Road Networks from Remote Sensor Data with Deep Learning

In this thesis we address the problem of semantic segmentation in geospatial data. We investigate different deep neural network architectures and present a complete pipeline for extracting road network vector data from satellite RGB orthophotos of urban areas. Firstly, we present a network based on the SegNeXt architecture for the semantic segmentation of the roads. A novel loss function is introduced for training the network. The results show that the proposed network produces on average better results than other state-of-the-art semantic segmentation techniques. Secondly, we propose a fast post-processing technique for vectorizing the rasterized segmentation result, removing erroneous lines, and refining the road network. The result is a set of vectors representing the road network. We have extensively tested the proposed pipeline and provide quantitative comparisons with other state-of-the-art based on a number of known metrics. This work has been published and presented at the 14 th International Symposium on Visual Computing, 2019. Finally, we present an altogether different approach to road extraction. We reformulate the task of extracting vectorized road networks as a deep reinforcement learning problem with partially observable state-space and present our preliminary results and future work

The role of porosity and 3D cross-stent configuration of multiple overlapping uncovered stents in the management of complex aortic aneurysms – insights from haemodynamics

Background: Multiple overlapping uncovered stents (MOUS) have been introduced to manage complex aortic aneurysms with vital branches involvement. It has been shown that the porosity is a key determinant of the treatment outcome. However, the role of 3D cross-stent configuration remains unclear. Methods: One patient with a complex aortic aneurysm judged not suitable for open surgery nor endovascular repair was invited to participate this study. In total, four bare metal stents were deployed. 3D lesion geometry was reconstructed based on pre- and post-operative CTA, and the zero-pressure configuration was recovered using an inverse procedure. Local haemodynamic parameters, including wall shear stress (WSS), oscillatory shear index (OSI), and particle relative resident time (RRT), as well as the vessel structural stress (VSS), were quantified using one-way fluid-structure interaction (FSI) analysis. In comparison to MOUS, a corresponding compact model was reconstructed by projecting inner layer stents to the most outer layer to form a single layer to eliminate the 3D cross-stent configuration and one-way FSI analysis was performed. Results: Results obtained showed that the porosity decreased linearly with the number of stents. When the 1st stent was deployed, the mean velocity decreased 36.4% and further reduction of 49.3%, 59.8%, and 62.8% were observed when the 2nd, 3rd and 4th stents were deployed. WSS also decreased with the number of stents deployed, and both OSI and RRT increased, but the increase was very minor with the 4th stent. MOUS deployment induced high VSS concentration in the landing zone while the VSS and pressure in the sac remained nearly unchanged. The compact model yielded a small difference in the value of flow-related parameters and 10%-20% reduction in VSS. Conclusion: Compared with porosity, the 3D cross-stent of MOUS configuration plays a minor role in the modulation of local haemodynamics. A compact model does not reduce high VSS concentration in the diseased region significantly.This study was supported by British Heart Foundation (BHF) (PG/18/14/33562), Engineering and Physical Sciences Research Council (EPSRC) (EP/P021654/1) and National Institute for Health Research (NIHR) Cambridge Biomedical Research Centre

Biofiltration of reduced sulphur compounds and community analysis of sulphur-oxidizing bacteria.

http://dx.doi.org/10.1016/j.biortech.2010.12.018The present work aims to use a two-stage biotrickling filters for simultaneous treatment of hydrogen sulphide (H2S), methyl mercaptan (MM), dimethyl sulphide (DMS) and dimethyl disulphide (DMDS). The first biofilter was inoculated with Acidithiobacillus thiooxidans (BAT) and the second one with Thiobacillus thioparus (BTT). For separate feeds of reduced sulphur compounds (RSC), the elimination capacity (EC) order was DMDS > DMS > MM. The EC values were 9.8 gMM-S/m3/h (BTT; 78% removal efficiency (RE); empty bed residence time (EBRT) 58 s), 36 gDMDS-S/m3/h (BTT; 94.4% RE; EBRT 76 s) and 57.5 gH2S-S/m3/h (BAT; 92% RE; EBRT 59 s). For the simultaneous removal of RSC in BTT, an increase in the H2S concentration from 23 to 293 ppmv (EBRT of 59 s) inhibited the RE of DMS (97–84% RE), DMDS (86–76% RE) and MM (83–67% RE). In the two-stage biofiltration, the RE did not decrease on increasing the H2S concentration from 75 to 432 ppmv

Improvement of local budget filling

This chapter describes the biological removal of sulphur compounds from gas streams. First, an overview is given of the toxicity of sulphur compounds to animals and humans whereafter biological and industrial formation routes for (organic) sulphur compounds are given. Microbial degradation routes of volatile organic sulphur compounds under both aerobic and anaerobic conditions are presented. Finally, the most commonly applied processes for sulphur removal from gaseous streams are discussed and an overview is given of operating experiences for biological gas treatment systems. The chapter concludes with some remarks on future developments

Experimental Study on Optimization of Phosphogypsum Suspension Decomposition Conditions under Double Catalysis

Phosphogypsum (PG) is not only a solid waste discharged from the phosphate fertilizer industry, but also a valuable resource. After high-temperature heat treatment, it can be decomposed into SO2 and CaO; the former can be used to produce sulfuric acid, and the latter can be used as building materials. In this paper, the catalytic thermal decomposition conditions of phosphogypsum were optimized, and the effects of the reaction temperature, reaction atmosphere, reaction time and carbon powder content on the decomposition of phosphogypsum were studied. The research shows that the synergistic effect of carbon powder and CO reducing atmosphere can effectively reduce the decomposition temperature of phosphogypsum. According to the results of the orthogonal test under simulated suspended laboratory conditions, the factors affecting the decomposition rate of phosphogypsum are temperature, time, atmosphere and carbon powder content in turn, and the factors affecting the desulfurization rate are time, temperature, atmosphere and carbon powder content in turn. Under laboratory conditions, the highest decomposition rate and desulfurization rate of phosphogypsum are 97.73% and 97.2%, and the corresponding reaction conditions are as follows: calcination temperature is 1180 °C, calcination time is 15 min, carbon powder content is 4%, and CO concentration is 6%. The results of thermal analysis of phosphogypsum at different temperature rising rates show that the higher the temperature rising rate, the higher the initial temperature of decomposition reaction and the temperature of maximum thermal decomposition rate, but the increase in the temperature rising rate will not reduce the decomposition rate of phosphogypsum

Proceedings of the 2nd Chinese-Austrian Workshop on Environmental Odour: Odour Emission - Dispersion - Impact Assessment - Abatement

Environmental odour is perceived as major nuisance by rural as well as by urban populations. The sources of odorous substances are manifold. In urban areas restaurants, small manufacturing businesses and other sources can be found inside residential areas. In the suburbs we can expect waste water treatment plants, landfill sites and other infra structures as major causing sources. These problems are often aggravated be the accelerated growth of cities. In rural spaces, livestock farming and the spreading of manure on the fields is blamed for severe odour nuisance. As a matter of fact, environmental odours are considered to be a common cause of public complaints by residents to local authorities, regional or national environmental agencies. In the 1st Chinese-Austrian Workshop on Environmental Odour held in Tianjin, China in February 2015 this environmental issue was addressed to compile experiences in this field. Participants from several universities as well as state agencies took part. The goal of this workshop was to establish cooperations in this field. One of the major results of this workshop was a bilateral joint project between the University of Science and Technology Beijing and Austrian partner organisations. The proceedings of this workshop were published in Volume 8 of the Austrian Contributions to Veterinary Epidemiology, a journal, which offers open access to all papers. In February 2016, the 2nd Chinese-Austrian Workshop on Environmental Odour was held in Shanghai, as one of the hotspots of environmental odour research in China. The workshop was hosted by Prof. Dr. Pinjing He, Institute of Waste Treatment & Reclamation at the College of Environmental Science and Engineering, Tongji University in Shanghai. The workshop included the following topics (1) Characterisation of odour sources by emission factors and emission models, (2) Monitoring of odour emission in diverse environments, (3) Equipment and methods of odour measurement, and (4) Assessment of the relevant stimuli concentration and the odour impact criteria. Prof. Dr. Pinjing He and his team deserve gratitude for the successful organisation on site and his Austrian counterpart Prof. Dr. Günther Schauberger from the University of Veterinary Medicine Vienna for the initiation and organisation of the meeting. Both are the guest editors for this issue. The workshop as well as Volume 9 of the Austrian Contributions to Veterinary Epidemiology was partly funded by Eurasia-Pacific Uninet as a network, which aims at establishing contacts and scientific partnerships between Austrian universities and member institutions in East Asia, Central Asia, South Asia and the Pacific region. In the light of the current air quality crisis confronting China and the world, I am confident that such bilateral efforts are an incentive for finding future solutions by cooperation of our two countries