Fair Scheduling in Cellular Systems in the Presence of Noncooperative Mobiles

We consider the problem of ``fair'' scheduling the resources to one of the many mobile stations by a centrally controlled base station (BS). The BS is the only entity taking decisions in this framework based on truthful information from the mobiles on their radio channel. We study the well-known family of parametric alpha-fair scheduling problems from a game-theoretic perspective in which some of the mobiles may be noncooperative. We first show that if the BS is unaware of the noncooperative behavior from the mobiles, the noncooperative mobiles become successful in snatching the resources from the other cooperative mobiles, resulting in unfair allocations. If the BS is aware of the noncooperative mobiles, a new game arises with BS as an additional player. It can then do better by neglecting the signals from the noncooperative mobiles. The BS, however, becomes successful in eliciting the truthful signals from the mobiles only when it uses additional information (signal statistics). This new policy along with the truthful signals from mobiles forms a Nash equilibrium (NE) that we call a Truth Revealing Equilibrium. Finally, we propose new iterative algorithms to implement fair scheduling policies that robustify the otherwise nonrobust (in presence of noncooperation) alpha-fair scheduling algorithms.

Third post-Newtonian gravitational waveforms for compact binary systems in general orbits: Instantaneous terms

We compute the instantaneous contributions to the spherical harmonic modes of gravitational waveforms from compact binary systems in general orbits up to the third post-Newtonian (PN) order. We further extend these results for compact binaries in quasielliptical orbits using the 3PN quasi-Keplerian representation of the conserved dynamics of compact binaries in eccentric orbits. Using the multipolar post-Minkowskian formalism, starting from the different mass and current-type multipole moments, we compute the spin-weighted spherical harmonic decomposition of the instantaneous part of the gravitational waveform. These are terms which are functions of the retarded time and do not depend on the history of the binary evolution. Together with the hereditary part, which depends on the binary's dynamical history, these waveforms form the basis for construction of accurate templates for the detection of gravitational wave signals from binaries moving in quasielliptical orbits.

Expanding adoption of drinking water treatment systems in developing countries: a case study from Tamil Nadu, India

Household-level water treatment and safe storage systems (HWTS) are simple, local, user-friendly, and low cost options to improve drinking water quality at the point of use. However, despite conclusive evidence of the health and economic benefits of HWTS, and promotion efforts in over 50 countries in the past 20 years, implementation outcomes have been slow, reaching only 5-10 million regular users. This study attempts to understand the barriers and drivers affecting HWTS implementation. Using a case study example of a biosand filter program in southern India, system dynamics modelling is shown to be a useful tool to map the inter-relationships of different critical factors and to understand the dissemination dynamics. It is found that the co-existence of expanding quickly and achieving financial sustainability appears to be difficult to achieve under the current program structure.

A systems approach to characterise the dissemination process of household water treatment systems in developing countries

Abstract: Starting in the 1980s, household-level water treatment and safe storage systems (HWTS) have been developed as simple, local, user-friendly, and low cost options to improve drinking water quality at the point of use. However, despite conclusive evidence of the health and economic benefits of HWTS, and promotion efforts in over 50 countries in the past 20 years, implementation outcomes have been slow, reaching only 5-10 million regular users. This study attempts to understand the barriers and drivers affecting HWTS implementation. Although existing literature related to HWTS and innovation diffusion theories proposed ample critical factors and recommendations, there is a lack of holistic and systemic approach to integrate these findings. It is proposed that system dynamics modelling can be a promising tool to map the inter-relationships of different critical factors and to understand the structure of HWTS dissemination process, which may lead to identifying high impact, leveraged mitigation strategies to scale-up HWTS adoption and sustained use.

Quota and Licensing Systems in the VIII Division European Anchovy

Paper presented at 12th Annual Conference of EAERE 2003 Bilbao (Spain)

Adsorptive Media Investigations and Testing for Improved Performance of Stormwater Treatment Systems in the Tahoe Basin

Retrofit activities, such as improving hydrology and incorporating more advanced treatment methods into systems where feasible, may improve phosphorus (P) removal performance of current Best Management Practices (BMPs). In the recent past, chemical treatment systems such as chemical dosing and the use of adsorptive media have become more prevalent for treating stormwater and hold promise for improving the P removal performance of stormwater treatment BMPs (Bachand et al., 2005; Patel et al., 2005). Our primary objective for this project has been to investigate whether adsorptive media hold any promise for improving P removal performance of stormwater basins and treatment wetlands at Lake Tahoe.... (PDF contains 99 pages)

Assessing the sustainability of brackish water aquaculture systems in the Phillipines. Working Paper 1: A typology of brackish-water pond aquaculture systems in the Philippines

Aquaculture in the Philippines is a long-standing activity but has witnessed relatively recent, rapid, technical change with the introduction of hatchery technology and commercial feed-mills changing the production possibilities for a fishpond operator. We are confronted with a diversity of aquaculture practices in the coastal areas of the Philippines, with new technologies being incorporated into more traditional systems. As a first step to understanding the sector, we therefore present a typology of farming systems with the motivation of generating domains (farm “types”) over which we can compare performance on a number of indicators. Our typology, restricted to brackish-water pond systems, is constructed using multivariate methods (principal components analysis, cluster analysis). Eight variables are used relating to the management of the farm across all the major factors of production. A stratified net sample of 136 observations provides the data for the analysis, from a farm-level survey carried out between January and June 2003 in the two main brackish-water production regions in the Philippines. We define five farm types from this analysis. In later work we will show how the use of this typology can be used for comparative study of economic, social and ecological performance at the farm-level. [PDF contains 42 pages]

Assessing the sustainability of brackish water aquaculture systems in the Philippines. Working Paper 4: Aquaculture and poverty - a case study of five coastal communities in the Philippines

After reviewing the rather thin literature on the subject, we investigate the relationship between aquaculture and poverty based on a case study of five coastal communities in the Philippines. The analysis relies on a data set collated through a questionnaire survey of 148 households randomly selected in these five communities. The methodological approach combines the qualitative analysis of how this relationship is perceived by the surveyed households and a quantitative analysis of the levels and determinants of poverty and inequality in these communities. There is overwhelming evidence that aquaculture benefits the poor in important ways and that it is perceived very positively by the poor and non-poor alike. In particular, the poor derive a relatively larger share of their income from aquaculture than the rich, and a lowering of the poverty line only reinforces this result. Further, a Gini decomposition exercise shows unambiguously that aquaculture represents an inequality-reducing source of income. We believe that the pro-poor character of brackish water aquaculture in the study areas is explained by the fact that the sector provides employment to a large number of unskilled workers in communities characterized by large surpluses of labour. Our results also suggest that the analysis of the relationship between aquaculture and poverty should not focus exclusively on the socio-economic status of the farm operator/owner, as has often been the case in the past. [PDF contains 51 pages]

The nature of small-scale farmer managed irrigation systems in North West Province, Sri Lanka and potential for aquaculture

RRAs were carried out in two Small Tank Cascade systems (STCs) of North West Province, Sri Lanka (less than 1000 ha total watershed area). A total of 21 tanks and 7 villages were investigated with primary emphasis on two upper watershed communities. The two systems differ primarily in their resource base; namely rainfall, natural forests and proximity to large scale perennial irrigation resources. [PDF contains 86 pages]