Law, technology and water conflicts in developing societies: a case study of tank systems in Tamil Nadu

The study examines the relationship between law, technology and water conflicts from colonial days to the present in traditional (water) tank systems in the south Indian state of Tamil Nadu. Tanks are man-made water systems developed for irrigation and many other purposes in semi-arid areas. The thesis adopts a historical approach to study the development of law, particularly property rights, and takes an empirical approach to investigate the tank conflicts. Archival documents on irrigation development, Case laws, Focus Group Discussions, Open ended Interviews and Field visits to selected tank chains are used as source material for the discussion. Case studies of conflicts are described and analyzed at three levels - Vaigai river basin for a macro level, Kothai Anicut system in Cauvery basin for a meso level, and twenty other interconnected tanks for a micro-level. The thesis deviates from the conventional understanding that tanks as traditional systems as simple and local technologies but considers them to be complex. It argues that the use of commonly held systems such as tanks within the colonial and post colonial laws as state ownership has been the source of many conflicts. In particular, it finds most tank conflicts are a product of progressive and absolute state control over water and the systems established using colonial land revenue administrative law. The law continues to treat tanks as pieces of landed property held by state and the individuals rather than as technology systems that presupposed the regime of property rights introduced after the colonial times. The modern interventions in water including the reservoir building, and altering the hydraulics of rivers and streams aggravate tank conflicts and lead to their further detriment. The study brings the focus to ground realities, and offers new perspectives on understanding tank systems in dynamic ways.

Departure and approach procedures for unmanned aircraft systems in a visual-flight-rule environment

This paper assesses the departure and approach operations of unmanned aircraft systems in one of the most challenging scenarios: flying under visual flight rules. Inspired by some existing procedures for (manned) general aviation, some automatic and predefined procedures for unmanned aircraft systems are proposed. Hence, standardized paths to specific waypoints close to the airport are defined for departure operations, just before starting the navigation phase. Conversely, and for the approach maneuvers, a first integration into a holding pattern near the landing runway (ideally, above it) is foreseen, followed by a standard visual-flight-rule airfield traffic pattern. This paper discuses the advantages of these operations, which aim to minimize possible conflicts with other existing aircraft while reducing the pilot-in-command workload. Finally, some preliminary simulations are shown in which these procedures have been successfully tested with simulated surrounding traffic.

Design, analysis and evaluation of sigma-delta based beamformers for medical ultrasound imaging applications

The inherent analogue nature of medical ultrasound signals in conjunction with the abundant merits provided by digital image acquisition, together with the increasing use of relatively simple front-end circuitries, have created considerable demand for single-bit  beamformers in digital ultrasound imaging systems. Furthermore, the increasing need to design lightweight ultrasound systems with low power consumption and low noise, provide ample justification for development and innovation in the use of single-bit  beamformers in ultrasound imaging systems. The overall aim of this research program is to investigate, establish, develop and confirm through a combination of theoretical analysis and detailed simulations, that utilize raw phantom data sets, suitable techniques for the design of simple-to-implement hardware efficient  digital ultrasound beamformers to address the requirements for 3D scanners with large channel counts, as well as portable and lightweight ultrasound scanners for point-of-care applications and intravascular imaging systems. In addition, the stability boundaries of higher-order High-Pass (HP) and Band-Pass (BP) Σ−Δ modulators for single- and dual- sinusoidal inputs are determined using quasi-linear modeling together with the describing-function method, to more accurately model the  modulator quantizer. The theoretical results are shown to be in good agreement with the simulation results for a variety of input amplitudes, bandwidths, and modulator orders. The proposed mathematical models of the quantizer will immensely help speed up the design of higher order HP and BP Σ−Δ modulators to be applicable for digital ultrasound beamformers. Finally, a user friendly design and performance evaluation tool for LP, BP and HP  modulators is developed. This toolbox, which uses various design methodologies and covers an assortment of  modulators topologies, is intended to accelerate the design process and evaluation of  modulators. This design tool is further developed to enable the design, analysis and evaluation of  beamformer structures including the noise analyses of the final B-scan images. Thus, this tool will allow researchers and practitioners to design and verify different reconstruction filters and analyze the results directly on the B-scan ultrasound images thereby saving considerable time and effort.

Assessing local food systems in China for building healthy mega-cities

Despite the long-lasting concern for food security in China at the national level, policy attempts to cope with this issue have often resulted to be ineffective. More importantly, they have rarely addressed the question from a local perspective. International experiences of urban food strategies proved to be quite efficacious in enhancing the local provision of food and improving the overall city sustainability by shortening the supply chain, preserving peri-urban areas and improving the nutrition of citizens. By reviewing existing practices of city farming in China, mainly ascribable to urban agriculture experiences, the intention of this paper is to reflect upon the challenges of implementing more comprehensive local food systems. In the conclusion the paper argues that, given the current institutional, socio-economic, and environmental constrains of Chinese cities there is a need of introducing holistic planning tool to assess local food systems in order to ensure the building of real healthy cities.