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28.05.2014 14:00 Stefan Savev |
Using Random Projections to Make Sense of High-Dimensional Big Data It is hard to understand what is hidden in big high dimensional data. However, a moderate number of simple one dimensional projections is enough to answer hard questions about the data via techniques such as visualization, classification and clustering. Random projections have emerged as an extremely effective component of many algorithms for high dimensional data. For example, they are used in the context of nearest neighbor search (via locality sensitive hashing), dimensionality reduction and clustering. The goal of the talk is to give a pleasant journey into the rich area of random projections via many graphical illustrations and intuitive examples. We present how and why random projections work and where they break. We discuss several interesting properties of high dimensional data. For example, why data in high dimensions is likely to look Gaussian when projected in low dimensions; how to spot interesting patterns in high dimensional data by projecting into a lower dimension; and how to choose meaningful low dimensional projections. The method of random projections has a number of good properties: 1) scalability; 2) it reduces the machine learning problem to search and can take advantage of existing infrastructure; 3) it is relatively simple to implement and 4) it is robust to noisy data. |
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25.11.2014 10:30
Jennifer L. Irish, Ph.D. |
Tropical cyclone flooding hazard assessment in a changing climate
Reliable tropical cyclone flooding hazard assessments are essential for planning, management, and engineering to ensure coastal resilience. Yet, the range of, and uncertainty in, future climate and sea-level conditions present a challenge for assessing future coastal flooding probabilities. Here, methods will be presented for incorporating sea-level rise and time-varying hurricane conditions into extreme-value flood statistics. A joint probability approach will be used with surge response functions to define time-varying continuous probability density functions for hurricane flood elevation. Finally, future challenges understanding future coastal hazards risk will be discussed.
Jennifer Irish is an Associate Professor at the Department of Civil and Environmental Engineering at Virginia Tech. For further information please visit: http://www.coastal.cee.vt.edu/people.html |
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13.06.2014 14:00
Adrien Labaeye Transition Lab |
Digital commons for an urban transition towards sustainability
Adrien Labaeye from the Transition Lab in Berlin will present the work of the Transition Lab and his project about urban transition. For further information see: http://transitionlab.wordpress.com/2014/05/07/research-in-focus-1-digital-commons-for-an-urban-transition-towards-sustainability/ |
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22.05.2014 14:00
Bettina Hamann TU Berlin |
Urban Management at the Technical University Berlin Bettina Hamann (Dr.ing landscape planning) will present the Urban Management Programme of the Technical University Berlin which she is coordinating. The programme offers training programs on specific aspects of urban management for foreign experts. For further information see: http://www.urbanmanagement.tu-berlin.de/menue/urban_management_at_tu_berlin/ |
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3.04.2014 14:00 Michael Stauffacher ETH Zürich |
Research for sustainable development: how social sciences can complement natural and engineering sciences Michael Stauffacher, PhD in sociology, working as senior scientist in the Department of Environmental Systems Science at the ETH Zürich (Natural and Social Science Interface & Transdisciplinarity Lab) and at moment guest research at PIK (RD IV). For further information see http://www.uns.ethz.ch/StauffacherM |
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12.03.2014 14:00 Sönke Dangendorf Universität Siegen |
170 years of storm activity in the North Sea: observations versus reanalysis The detection of potential long-term changes in historical storm statistics and storm surges plays a vitally important role for protecting coastal communities. Due to the absence of long homogeneous wind records, the scientific community proceeded to the evaluation of (i) more homogeneous storminess proxies typically calculated from sea level pressure readings, or (ii) reanalysis wind fields as calculated from global weather models with the assimilation of sea level pressure, sea surface temperature and sea ice cover. For the North Sea region both sources of information provide competing results with significant increasing trends since the late 19th century in storminess measures derived from the 20th century reanalysis data set and non-significant trends from those directly inferred from single station observations. Here, an independent measure of storminess is analyzed. By applying a tidal analysis to high and low water observations in the North Sea, a novel 170 year old storm surge record is reconstructed and analyzed. Furthermore, a methodological framework is presented, how water level observations may provide information about the homogeneity of reanalysis data sets. Sönke Dangendorf is a civil engineer working as a researcher at the Research Institute for Water and Environment (fwu) at the University of Siegen. |
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13.12.2013 14:00 Dr. Helga Fink |
Climate Change in Northern India and Adaptation Needs The CCA-NER project in North-East India takes an integrated approach to climate adaptation and strengthening resilience. It addresses a broad range of sectors, designing interventions and providing capacity building, e.g. in water resources and forest management, agriculture and crop breeding, disaster preparedness, greening of value chains, livelihood diversification, and strengthening of institutions. Lessons learned and difficulties from the first two years will be discussed and will focus on, e.g. the visibility of initial climate change effects, the willingness of stakeholders and project partners to mainstream climate adaptation into their ongoing activities. Helga Fink is a social scientist with a PhD in medical and social anthropology. Her working focus is on sustainable development policies. She has longstanding expertise in rural and urban water and sanitation supply, water resource management, management of natural resources and biodiversity, environment protection and adaptation to climate change and mitigation. She has recently been advising the African Development Bank (AfDB) on Green Economy issues and integrated safeguard policy, and she has also a long standing experience of collaboration with KfW and bi-and multinational donors in the fields of technical cooperation and co-financing. |
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12.06.2013 14:00 University of Florida |
Coastal Inundation for Current and Future Climates More than 50% of the world's population live within 100 km of coastlines. Coastal communities are subject to increasing risk of coastal inundation due to storms, tsunamis, climate change, and growing coastal population and development. Recent studies have suggested that climate change would lead to increased intensity yet less frequent storms as well as sea level rise along the Atlantic and Gulf coasts of the U.S. The Advanced Coastal Environment Systems (ACES) group at the University of Florida has been studying the coastal inundation for current and future climates, using several different methods to assess the probabilistic risk of coastal inundation, while working with various stakeholders in South Florida coastal communities on adaptation methodologies. This talk will describe the various methods used for coastal mapping: (1)The Joint Probability Method with optimal sampling (JPM-OS), with historical tropical storm data during 1950-2009; (2)The JPM-OS method, with storm data generated by a statistical tropical storm model with a focus on the storms during the 1990-2009 period; and (3)Using 2020-2040 tropical storm data produced by a global-regional atmospheric modeling system. Preliminary results show that the 100-year coastal inundation in Miami area can increase by 0.5-1.0 m due to climate change, without considering sea level rise. Sea level rise of 0.3-1.5 m will further exacerbate the coastal communities. Impact on the coastal infrastructure and environment (beaches, estuaries), as well as adaptation methodologies, will also be addressed. |
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26.04.2013 11:00 University of Stellenbosch |
Reshaping urban infrastructure for sustainability
It is accepted that transitioning to more efficient and sustainable metabolic flows through cities will be key to building up more sustainable cities. However, resource flows are conducted through cities by urban infrastructures. It follows that urban infrastructures will need to be reconfigured to achieve this transition. Urban infrastructures, however, are large technical systems that suffer from ‘lock in’ and are rarely managed by people with knowledge about alternatives. At the same time, as an alternative the SMART City agenda has emerged from the large technology companies that promises not only investments in new modern infrastructures, but also resource efficiency and decarbonisation. This talk will apply the notion of decoupling to city-level infrastructures, and then raise some critical questions about the potential and desirability of the Smart City solutions that have already started to be implemented. |
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26.03.2013 14:00 IASS |
Sustainable Atmosphere for the Kathmandu Valley (SusKat) Kathmandu City, the capital city of Nepal, is among the most polluted cities in the world. However there are only few past studies that provide basic understanding of air pollution in the Kathmandu Valley, which is not sufficient for designing effective mitigation measures (e.g., technological, financial, regulatory, legal and political measures, planning strategies) that fit to local context. The Institute for Advanced Studies (IASS) has initiated an end-to-end study, called "Sustainable atmosphere for the Kathmandu valley (SusKat)", which is being implemented in collaboration with about 20 groups from 8 different countries. This presentation will provide an overview of issue, our approach, and expected outcomes of the initiative. Some preliminary results of the ongoing SusKat-ABC atmospheric characterization campaign in Nepal will also be presented. |
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15.02.2013 14:00 IASS |
Growth: A Discussion of the Margins of Economic and Ecological Thought In the late 1960s a debate about the long-term feasibility and desirability of economic growth as a one-size-fits-all economic policy emerged. It was argued that economic growth was one of the underlying causes of ecological and social problems faced by humanity. The issue remained strongly disputed until the inception of the Sustainable Development discourse by which the debate was politically settled. Nevertheless, given that many ecological and social problems remain unsolved and some have become even more severe, there are renewed calls for the abandoning of the economic growth commitment, particularly in already affluent countries. This chapter summarises the growth debate hitherto and examines two alternatives, the steady-state economy proposed by Herman Daly and economic de-growth proposed by Serge Latouche. In spite of recent disputes between the Anglo-Saxon steady-state school and the emerging continental de-growth school, it is argued, consistent with recent contributions on the issue, that steady-state and de-growth are not mutually exclusive but inevitably complements. The steady-state has the advantage of comprehensive theoretical elaboration, while de-growth has the advantage of an attractive political slogan which has re-opened the debate on the issue. Latouche is also a social thinker who gives a voice to the critiques of economic growth contained in the notion of development from outside Europe and the United States. The steady-state economy, and de-growth are held by some analysts to be beyond what is politically feasible. Although this argument is valid, it fails to recognise that past desirable societal changes were made possible through reflexive societal processes conducive to collective action and institutional change. It is concluded that the debate must ultimately rest in the physical quantities that a given economy needs for the ‘good life’ in the long run, how to decide on these quantities, how to achieve them, and how to maintain an approximate global steady-state. Finally, some recommendations for further research along with some reflections on the potential role of scholars are provided. |
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18.01.2013 14:00 Luis Felipe Melgarejo |
Emergency shelter planning and climatic extreme events in developing countries: a regional analysis from Chía - Colombia Based on climate impacts and mitigation modelling revealed in IPCC 2007 and SREX 2012 reports, developing countries with high exposition to hydrometeorological disasters have begun to incorporate in their local planning, adaptive mechanisms on risk management and resilience enhancement, such as natural buffer areas for flood protection, risk-oriented land use planning, landslides monitoring of vulnerable settlements among others. Despite the latter, the first decade of the 21st century has been decisive in proving that climate extreme events (heat waves, windstorms with higher intensity and/or frequency, mass floods, landslides, long-lasting droughts and precipitations) are increasingly overcoming local and national emergency systems in vulnerable regions. Future needs on temporary emergency shelter and microclimatic scenarios as well as public policy assessments and experiences from a fluvial floodprone region in Colombia are the basis of study in this research. This project aims to analyse the spatial and humanitarian characterization that critical public infrastructure (sport halls, health centres, etc.) have during fluvial floods and its institutional and community-based appraisal for mitigating the risks of hydrometeorological disasters. Characterizing the spatial-human-environment dynamics in the use and localization of public infrastructure for transitional shelter and recovery purposes is becoming a global practice in order to improve disaster management plans and enhance adaptive capacities of local authorities. |
