Asymptotics of Bayesian Error Probability and 2D Pair Superresolution

This paper employs a recently developed asymptotic Bayesian multi-hypothesis testing (MHT) error analysis to treat the problem of superresolution imaging of a pair of closely spaced, equally bright point sources. The analysis exploits the notion of the minimum probability of error (MPE) in discriminating between two competing equi-probable hypotheses, a single point source of a certain brightness at the origin vs. a pair of point sources, each of half the brightness of the single source and located symmetrically about the origin, as the distance between the source pair is changed. For a Gaussian point-spread function (PSF), the analysis makes predictions on the scaling of the minimum source strength, expressed in units of photon number, required to disambiguate the pair as a function of their separation, in both the signal-dominated and background-dominated regimes. Certain logarithmic corrections to the quartic scaling of the minimum source strength with respect to the degree of superresolution characterize the signal-dominated regime, while the scaling is purely quadratic in the background-dominated regime. For the Gaussian PSF, general results for arbitrary strengths of the signal, background, and sensor noise levels are also presented.Comment: Submitted to Optics Express, March 18, 201

Skin Uncertainty in Multi-Layered Commingled Reservoirs with Non-Uniform Formation Damage

Imperial Users onl

Strategies for the Replication of Urban Environmental Innovations - A Case of Community-based Decentralized Composting in Dhaka

Traditionally sanitary services are provided by the State or State owned bodies. However, with the ever increasing population and waste generation rates coupled with lack of financial resources and infrastructure, poor community participation the municipalities are unable to provide a good service. As a result major fraction of waste remains uncollected on streets and sewer systems. Many bigger cities in Asia, South and Southeast-Asia in particular, are facing this situation. Hence, to bring the much needed additional resources and also to improve the efficiency of the system, involvement of private sector in providing these civic services has become a necessity. Waste Concern (WC), a non-government organization in Dhaka had initiated community based composting by partnering with Public Works Department (PWD), Dhaka City Corporation (DCC) and fertilizer manufacturing industry. With improved community participation, they have successfully demonstrated the marketing of compost generated from solid waste and increasing demand for the same in the market testimonies the fact that the whole process is a success with all partners sharing various benefits. As this attempt by WC has been identified as an innovative urban practice by many international agencies, other cities from the developing countries are showing interest in this useful practice. In this paper attempts are made to understand the process of Dhakas Community-based Decentralized Composting (DCDC) model, its socio-economic impacts, long term intra-sectoral implications, necessary conditions, and to identify strategies/measures to replicate DCDC in the other developing cities of Asia. DCDC is more labour intensive and less capital intensive option with promising employment generation. From the analysis it was found that this method of waste management is suitable for cities with poor waste management efficiency, considerable activity of rag picking by informal sector and existence of urban poor deriving livelihood on scavenging activity. There should also be enough demand for the compost generated and also the acceptability among partners. Based on the socio-economic analysis and personal interviews with all actors involved in DCDC, the following strategies/measures are identified as requirement for its replication and long term sustainability in the other developing cities in Asia selection of appropriate technology; utilization of local human resources; public-private-community partnership and appropriate risk sharing; community participation; need for champion organization (Ambassador); entrepreneurship in the approach; product quality control; sustainable benefits sharing; regulatory framework to promote partnerships; interfacing the other complementing sectors; analyzing the demand-supply dynamics; pricing policies to regulate compost price; assessment of macro-economic impacts.Community Participation, Decentralized Composting, Dhaka, Replication Strategies, Solid Waste Management