9 research outputs found
Implementation-Oblivious Transparent Checkpoint-Restart for MPI
This work presents experience with traditional use cases of checkpointing on
a novel platform. A single codebase (MANA) transparently checkpoints production
workloads for major available MPI implementations: "develop once, run
everywhere". The new platform enables application developers to compile their
application against any of the available standards-compliant MPI
implementations, and test each MPI implementation according to performance or
other features.Comment: 17 pages, 4 figure
Modeling the contribution of ecological agriculture for climate change mitigation in cote d'Ivoire
The use of crop models is motivated by the prediction of crop production under climate
change and for the evaluation of climate risk adaptation strategies. Therefore, in the present
study the performance of DSSAT 4.6 was evaluated in a cropping system involving integrated
soil fertility management options that are being promoted as ways of adapting agricultural
systems to improve both crop yield and carbon sequestration on highly degraded soils
encountered throughout middle CĂŽte dâIvoire. Experimental data encompassed two seasons
in the Guinea savanna zone. Residues from the preceding vegetation were left to dry on plots
like mulch on an experimental design that comprised the following treatments: (i) herbaceous
savanna-maize, (ii)10 year-old of the shrub Chromolaena odorata fallow-maize (iii) 1 or 2
year-old Lalab pupureus stand-rotation, (iv) the legume L. pupureus -maize rotation; (v) continuous
maize crop fertilized with urea; (vi) continuous maize crop fertilized with triple superphosphate;
(vii) continuous maize crop, fertilized with both urea and triple superphosphate
(TSP); (viii) continuous maize cultivation. The modelâs sensitivity analysis was run to figure
out how uncertainty of stable organic carbon (SOM3) can generate variation in the prediction
of soil organic carbon (SOC) dynamics during the monitoring period of two years, within
the first soil layer and to estimate the most suitable value. The observed variations were of
0.05 % in total SOC within the short-term and acceptable dynamics of changes were obtained
for 0.80% of SOM3. The DSSAT model was calibrated using data from the 2007-2008
season and validated against independent data sets of yield of 2008-2009 to 2011-2012
cropping seasons. After the default values for SOM3 used in the model was substituted by the
estimated one from sensitivity analysis, the model predicted average maize yields of 1 454
kg ha-1 across the sites versus an observed average value of 1 736 kg ha-1, R2 of 0.72
and RMSE of 597 kg ha-1. The impact of fallow residues and cropping sequence on maize
yield was simulated and compared to conventional fertilizer and control data using historical
climate scenarios over 12 years. Improving soil fertility through conservation agriculture cannot
maintain grain yield in the same way as conventional urea inputs, although there is better
yield stability against high climate variability according to our results
Scalable Observation, Analysis, and Tuning for Parallel Portability in HPC
It is desirable for general productivity that high-performance computing applications be portable to new architectures, or can be optimized for new workflows and input types, without the need for costly code interventions or algorithmic re-writes. Parallel portability programming models provide the potential for high performance and productivity, however they come with a multitude of runtime parameters that can have significant impact on execution performance. Selecting the optimal set of parameters, so that HPC applications perform well in different system environments and on different input data sets, is not trivial.This dissertation maps out a vision for addressing this parallel portability challenge, and then demonstrates this plan through an effective combination of observability, analysis, and in situ machine learning techniques. A platform for general-purpose observation in HPC contexts is investigated, along with support for its use in human-in-the-loop performance understanding and analysis. The dissertation culminates in a demonstration of lessons learned in order to provide automated tuning of HPC applications utilizing parallel portability frameworks
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Tourism in contemporary cities. Proceedings of the International Tourism Studies Association Conference: University of Greenwich, London, UK 17â19 August 2016 Conference Proceedings
The 6th International Tourism Studies Association (ITSA) Biennial conference was held at the University of Greenwich, London, England from 17â19 August 2016. This was the first time that the conference had been held in Europe and it provided a unique opportunity to meet, hear from and network with tourism scholars and professionals from across Europe, Asia, Australasia, and North and South America. ITSA has a mission to encourage interaction and cooperation between developing and developed countries and the conference was successful in attracting 130 delegates from 29 countries.
The main theme of the conference was 'Tourism in Contemporary Cities' with four conference subâthemes of âTourism Cities and Urban Tourismâ, âThe Chinese Market for European Tourismâ, âRiver, Cruise and Maritime Tourismâ, and âHeritage Tourism in Citiesâ, The subthemes were chosen to reflect the unique location of the conference on the UNESCO Maritime Greenwich World Heritage Site, and London which is Europeâs most visited tourist destination. The conference also presented âDark Tourism and Citiesâ and âTourism and Communist Heritageâ as special sessions
Assessing progress towards meeting major international objectives related to nature and nature's contributions to people
In recognition of the importance of nature, its contributions to people and role in underpinning sustainable development, governments adopted a Strategic Plan on Biodiversity 2011-2020 through the Convention on Biological Diversity (CBD) containing 20 "Aichi Biodiversity Targets" and integrated many of these into the Sustainable Development Goals (SDGs) adopted through the United Nations in 2015. Additional multilateral environmental agreements (MEAs) target particular aspects of nature (e.g., Ramsar Convention on Wetlands; Convention on Migratory Species), drivers of biodiversity loss (e.g., Convention on International Trade in Endangered Species of Wild Fauna and Flora), or responses (e.g., World Heritage Convention). These various MEAs provide complementary fora in which governments strive to coordinate efforts to reduce the loss and degradation of nature, and to promote sustainable development. In this chapter, we assess, through a systematic review process and quantitative analysis of indicators, progress towards the 20 Aichi Targets under the Strategic Plan (and each of the 54 elements or components of these targets), targets under the SDGs that are relevant to nature and nature's contributions to people (NCP), and the goals and targets of six other MEAs. We consider the relationships between the SDGs, nature and the contributions of Indigenous Peoples and Local Communities (IPLCs) to achieving the various targets and goals, the impact of progress or lack of it on IPLCs, the reasons for variation in progress, implications for a new Strategic Plan for Biodiversity beyond 2020, and key knowledge gaps.For the 44 SDG targets assessed, including targets for poverty, hunger, health, water, cities, climate, oceans and land (Goals 1, 2, 3, 6, 11, 13, 14, 15), findings suggest that current negative trends in nature will substantially undermine progress to 22 SDG targets and result in insufficient progress to meet 13 additional targets (i.e. 80 per cent (35 out of 44) of the assessed targets) {3.3.2.1; 3.3.2.2}(established but incomplete). Across terrestrial, aquatic and marine ecosystems, current negative trends in nature and its contributions will hamper SDG progress, with especially poor progress expected towards targets on water security, water quality, ocean pollution and acidification. Trends in nature's contributions relevant to extreme event vulnerability, resource access, small-scale food production, and urban and agricultural sustainability are negative and insufficient for achieving relevant targets under SDGs 1, 2, 3, and 11. This has negative consequences for both the rural and urban poor who are also directly reliant on declining resources for consumption and income generation {3.3.2.2}. For a further 9 targets evaluated in SDGs 1, 3 and 11 a lack of knowledge on how nature contributes to targets (4 targets) or gaps in data with which to assess trends in nature (5 targets) prevented their assessment.Fil: Butchart, Stuart. London Metropolitan University; Reino UnidoFil: Miloslavich, Patricia. University of Western Australia; AustraliaFil: Reyers, Belinda. No especifĂca;Fil: Galetto, Leonardo. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - CĂłrdoba. Instituto Multidisciplinario de BiologĂa Vegetal. Universidad Nacional de CĂłrdoba. Facultad de Ciencias Exactas FĂsicas y Naturales. Instituto Multidisciplinario de BiologĂa Vegetal; ArgentinaFil: Subramanian, Suneetha M.. No especifĂca;Fil: Adams, Cristina. No especifĂca;Fil: Palomo, Maria Gabriela. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Oficina de CoordinaciĂłn Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; ArgentinaFil: McElwee, Pamela. No especifĂca;Fil: Meretsky, Vicky J.. No especifĂca;Fil: Morsello, Carla. No especifĂca;Fil: Nel, Jeanne. No especifĂca;Fil: Lynn Newberry, Teresa. No especifĂca;Fil: Pacheco, Diego. No especifĂca;Fil: Pyhala, Aili. No especifĂca;Fil: Rossi Heras, Sergio. No especifĂca;Fil: Roy, Joyashree. No especifĂca;Fil: Ruiz-MallĂ©n, Isabel. No especifĂca;Fil: Salpeteur, Matthieu. No especifĂca;Fil: Santos-Martin, Fernando. No especifĂca;Fil: Saylor. Kirk. No especifĂca;Fil: Schaffartzik, Anke. No especifĂca;Fil: Sitas, Nadia. No especifĂca;Fil: Speranza, Ifejika. No especifĂca;Fil: Suich, Helen. No especifĂca;Fil: Tittensor, Derek. No especifĂca;Fil: Carignano, Patricia. No especifĂca;Fil: Tsioumani, Elsa. No especifĂca;Fil: Whitmee, Sarah. No especifĂca;Fil: Wilson, Sarah. No especifĂca;Fil: Wyndham, Felice. No especifĂca;Fil: Zorondo-Rodriguez, Francisco. No especifĂca