1,202 research outputs found

    Singapore: A Story Unfolding

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    Earth's surface fluid variations and deformations from GPS and GRACE in global warming

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    Global warming is affecting our Earth's environment. For example, sea level is rising with thermal expansion of water and fresh water input from the melting of continental ice sheets due to human-induced global warming. However, observing and modeling Earth's surface change has larger uncertainties in the changing rate and the scale and distribution of impacts due to the lack of direct measurements. Nowadays, the Earth observation from space provides a unique opportunity to monitor surface mass transfer and deformations related to climate change, particularly the global positioning system (GPS) and the Gravity Recovery and Climate Experiment (GRACE) with capability of estimating global land and ocean water mass. In this paper, the Earth's surface fluid variations and deformations are derived and analyzed from global GPS and GRACE measurements. The fluids loading deformation and its interaction with Earth system, e.g., Earth Rotation, are further presented and discussed.Comment: Proceeding of Geoinformatics, IEEE Geoscience and Remote Sensing Society (GRSS), June 24-26, 2011, Shanghai, Chin

    CFD Predictions of Soot & CO Emissions Generated by a Partially-Fueled 9-Element Lean-Direct Injection Combustor

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    A study was undertaken to investigate the CO & soot emissions generated by a partially-fueled 9- element LDI (Lean-Direct Injection) combustor configuration operating in the idle range of jet engine conditions. In order to perform the CFD analysis, several existing soot/chemistry models were implemented into the OpenNCC (Open National Combustion Code). The calculations were based on a Reynolds-Averaged Navier Stokes (RANS) simulation with standard k-epsilon turbulence model, a 62- species jet-a/air chemistry, a 2-equation soot model, & a Lagrangian spray solver. A separate transport equation was solved for all individual species involved in jet-a/air combustion. In the test LDI configuration we examined, only five of the nine injectors were fueled with the major pilot injector operating at an equivalence ratio of near one and the other four main injectors operating at an equivalence ratio near 0.55. The calculations helped to identify several reasons behind the soot & CO formation in different regions of the combustor. The predicted results were compared with the reported experimental data on soot mass concentration (SMC) & emissions index of CO (EICO). The experimental results showed that an increase in either T3 and/or F/A ratio lead to a reduction in both EICO & SMC. The predicted results were found to be in reasonable agreement. However, the predicted EICO differed substantially in one test condition associated with higher F/A ratio

    Sparse Coding of Neural Word Embeddings for Multilingual Sequence Labeling

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    In this paper we propose and carefully evaluate a sequence labeling framework which solely utilizes sparse indicator features derived from dense distributed word representations. The proposed model obtains (near) state-of-the art performance for both part-of-speech tagging and named entity recognition for a variety of languages. Our model relies only on a few thousand sparse coding-derived features, without applying any modification of the word representations employed for the different tasks. The proposed model has favorable generalization properties as it retains over 89.8% of its average POS tagging accuracy when trained at 1.2% of the total available training data, i.e.~150 sentences per language

    Analysis of Inducible Nitric Oxide Synthase Gene Polymorphisms in Vitiligo in Han Chinese People

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    Background: Vitiligo is a chronic depigmented skin disorder with regional melanocytes depletion. The pathogenesis was not completely clarified. Recently, more and more evidence suggested that polymorphisms of some genes are associated with vitiligo risk. Here, we want to examine the association between the inducible nitric oxide synthase (iNOS) gene polymorphisms and the risk of vitiligo in Chinese populations. Methods and Principal Findings: In a hospital-based case-control study of 749 patients with vitiligo and 763 age- and sexmatched healthy controls, three polymorphisms of iNOS gene were genotyped by using the PCR-restriction fragment length polymorphism (PCR-RFLP) and mutagenically separated PCR (MS-PCR) methods, respectively. We found the iNOS-954 polymorphism was associated with a significantly higher risk of vitiligo (adjusted OR = 1.36, 95 % CI = 1.02–1.81). Furthermore, this association is more pronounced in vulgaris vitiligo, active vitiligo and vitiligo without other autoimmune diseases in the stratification study. Analysis of haplotypes showed increased risk for the C-1173C-954CEx16+14 (OR = 1.44, 95% CI = 1.01–1.74). In addition, the serum iNOS activity is significantly associated with iNOS-954 combined genotype (GC+CC) and is much higher in vitiligo patients than in the controls (P,0.01). Logistic regression analysis of iNOS activity showed increased risk between higher activity and iNOS-954 GRC variant genotype carriers (Ptrend,0.001). Conclusions and Significance: INOS gene polymorphisms may play an important role in the genetic susceptibility to th

    The Trouble with the MDGs: Confronting Expectations of Aid and Development Success

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    Growing concern that the Millennium Development Goals (MDGs) will not be achieved by 2015 should not obscure the bigger picture that development progress has been occurring at unprecedented levels over the past thirty or more years. At the same time, the MDGs may perhaps create an unnecessary pessimism toward aid by labeling many development successes as failures. The first MDG of halving the number of people living in poverty will probably be met globally, but for most developing countries to achieve this at the national level, the growth rates required are at the bounds of historical precedent. Additionally, there appears to be only a weak relationship between aid and rapid economic growth. A similar problem holds for many of the other education and health goals. For many countries, the rates of progress required to meet the MDGs by 2015 are extremely high compared to historical experience and there is only a tenuous relationship between expenditure and outcomes. Nevertheless, estimates that an additional $50 billion in aid per year is necessary to meet the MDGs are frequently misinterpreted to suggest that it is also sufficient. Most of the goals are unlikely to be reached, but this will probably not be due primarily to shortfalls in aid. This is in part because development is a long-term and complex process dependent on relieving more than a supply-side constraint on resources. Aid remains vital and contributes to development progress, but even considerable increases in aid are unlikely to buy these particular goals. Goal setting is also useful, but continuing to suggest that the MDGs can be met may undermine future constituencies for aid (in donors) and reform (in recipients). The MDGs might be better viewed not as realistic targets but as reminders of the stark contrast between the world we want and the world we have, and a call to redouble our search for interventions to close the gap.Millennium Development Goals poverty economic growth
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