Loss of chaos in combustion noise as a precursor of impending combustion instability

Combustion noise has been traditionally thought of as stochastic fluctuations present in the background of the dynamics in combustors amongst the flow, heat release and the chamber acoustics. Through a series of determinism tests, we show that these aperiodic fluctuations are in fact chaotic of moderately high dimensions (d0 ≅ 8–10). These chaotic fluctuations then transition to high amplitude combustion instability when the operating conditions are varied towards leaner equivalence ratios. Precursors to such a transition from chaos to dynamics dominated by periodic oscillations are of interest to designers and operators of combustors in estimating the boundaries of operability. We introduce a test for chaos, known as 0–1 test for chaos in the literature, as a measure of the proximity of the combustor to an impending instability. The measure is robust and shows a smooth transition for variation in flow conditions towards instability enabling thresholds to be set for operational boundaries

Burden and causes of maternal mortality and near-miss in a tertiary care centre of Kerala, India

Background: Reduction of maternal mortality remains a challenge for developing countries like India as per the sustainable development goals put forward by UN. Near-miss audit is emerging as a new tool for setting new protocols in reduction of MMR. This study aimed, to analyze the near miss events and mortality events which occurred in the study setting from January 2011 to December 2012, and to compare the causes that led to the events.Methods: A descriptive comparative study was conducted at SAT Hospital, Government Medical College, Thiruvananthapuram, a tertiary care center in Kerala, India on the data accounted for a period of 2 years, 2011 and 2012. Maternal near-miss during the period is studied according to WHO 2009 criteria and compared with the maternal deaths during the same time period. The data was recorded using structured proforma; the same proforma was used to record maternal mortality cases of the same period.Results: Total live births during the time period were 18,663. Eighty-eight near miss cases and 26 maternal deaths occurred during the study period. Incidence proportion of maternal near-miss was 4.71/1000 live births. Severe maternal outcome was 6 per1000. For every maternal death, there were 3.38 near-misses. Mortality index of our institute was 22.8% and maternal mortality ratio (MMR) of the study setting was 139/1 Lakh live births. Post-partum hemorrhage was the leading cause for near-miss and systemic diseases were the major contributors to mortality.Conclusions: It is evident from the present study that PPH, once the leading cause of maternal mortality is now the leading cause of maternal near miss and by improving the resources of FRUs it can be further reduced. Systemic diseases are emerging as a new threat to the obstetric population leading to mortality

What offers solution to the poverty reduction of the Haor people in Bangladesh? Seasonal migration or a new inshore economic livelihood policy

Researches from different disciplines are yet to provide a concrete standpoint on causal relationship between poverty and migration. With a market driven attitude, seasonal migration has been increasing dramatically with a hope to reduce the poverty. So far, research has not confirmed if migration helps to reduce poverty or poverty is forced to be migrated. Whatever the fact, it would be realistic that the local community will not migrate if they find better work opportunities with higher productivity for their livings. In this paper, an effort is made to discover the possible ways to make the local community in the Haor area to be productive, ensuring their stay in their homes. A development economic policy guideline is aimed to be provided in order to make the possible ways functional. Along drawing individual and household profile of migrant, a mixed method suggests that some interventions of food stamp, infrastructure facilities and cooperative activities are necessary for in-situ socio-economic development of the Haor people. The outcomes of the study are reliable to apply in underprivileged ecological areas in other developing countries alike

Different economic and policy perspectives in micro population for sustainable development: A study of the Haor livelihood in Bangladesh

Criteria of development approaches and their schemata have evolved out of historical social practices. Interpretation of social events is guided and constrained by the prevailing rationality which itself reflects the dominant constellation of power. With the course of change of time and modernization, a number of development approaches have taken place especially in the context of developing nations. However, the discourse of the development of a less number of populations who are having geographically disadvantaged, unskilled and physically challenged positions is always seen as critical, since it requires high investment from public subsidy but provides less public and private returns. Factually, without the development of these populations, state mission will be missed out. Considering this is an issue for research in the area of public policy and development studies, this study was conducted in Bangladesh with a scientific adoption of both quantitative and qualitative methods, intending to discover an approach that helps the particular group to develop without hampering the return to the investment made by the state. Although, this study was conducted in Bangladesh, the development approach discovered can be used to many other developing country contexts