29,389 research outputs found

    The environmental control and life-support system for a lunar base: What drives its design

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    The purpose of this paper is to identify and briefly discuss some of the ground rules and mission scenario details that become drivers of the environmental control and life support (ECLS) system design and of the logistics related to the design. This paper is written for mission planners and non-ECLS system engineers to inform them of the details that will be important to the ECLS engineer when the design phase is reached. In addition, examples illustrate the impact of some selected mission characteristics on the logistics associated with ECLS systems. The last section of this paper focuses on the ECLS system technology development sequence and highlights specific portions that need emphasis

    A rapid review of the background to source control

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    Background to researchThe start of the 21st Century witnessed a revolution in drainage practices with the implementation of sustainable drainage systems (SUDS). Prior to 2000, rainfall was managed by directing it away as quickly as possible in underground pipes. Increasing pressures such as watercourse pollution, stricter environmental laws, climate change and urbanisation called for a paradigm shift with Scotland leading the way for implementing SUDS. SUDS are designed to mimic natural drainage processes, managing rainfall in stages as it drains from a development. Collectively this process is called the stormwater treatment train. The first stage is source control, with stages two and three being site and regional controls respectively. Source control principally controls and treats polluted runoff at source (where the rain falls) and if designed and implemented correctly, protect watercourses and downstream SUDS through filtration, infiltration and storage. In Scotland, site and regional control SUDS have become business as usual, however uptake of the stormwater treatment train and the use of source control SUDS in practice is less routine than would be expected.Objectives of researchThe SUDS Working Party in Scotland is an interdisciplinary stakeholder platform to discuss issues relating to the SUDS agenda and promote their use. In 2009, a consultation paper on ‘Implementing the Water Environment and Water Services (Scotland) Act’ set out proposals to improve the sustainable management of Scotland’s water resources. The need for increased source control measures for the mitigation of diffuse pollution and climate change effects in urban areas was identified. To assist in this aspiration, the SUDS Working Party commissioned this study via CREW to identify opportunities and barriers to increasing the uptake of source control in Scotland. This report covers phase one of a three-phase study. It focuses on tracking the evolution of source control to gain an insight into enabling factors and obstacles for successful uptake of the systems. A literature review identified source control origins, the techniques available, and options for their application.Key findings and recommendationsIn the UK, research to validate the performance of source control measures began in the early 1990’s. This was enabled by stakeholder platforms such as the SUDS Working Party and the Scottish Universities SUDS Monitoring Group. By the mid-1990s, the SUDS concept was developed which included source control and outlined water quality, quantity and biodiversity / amenity benefits of the systems. By 2000, Scottish guidance was developed and by 2006 it became law to implement SUDS in all new developments. This was quickly followed by technical standards in 2007. SUDS for roads networks were addressed in 2010. Currently, many types of source control exist, most of which have been validated by research and are commonplace. The state of the art techniques such as rain gardens, green roofs and rainwater harvesting however, have had limited uptake in Scotland.It is evident that the enabling factors for the uptake of SUDS have been the result of top down drivers such as environmental initiatives and regulation. However, clarity surrounding the definition and application of source control as part of the stormwater treatment train is becoming a barrier to its uptake by practitioners. Extensive research provided a bottom up driver to validate effectiveness of the technologies for attenuating pollutants, mitigating flooding and creating habitats. Validation of emerging innovative techniques however, such as green roofs and rain gardens for different development types is limited in Scotland and this may prove to be a barrier in the future

    Hydrological and environmental issues of interbasin water transfers in India: a case of the Krishna River Basin

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    River basins / Water transfer / Environmental effects / Dams / Reservoirs / Water resources development / Irrigation requirements / Case studies / India / Krishna River / Godavari River

    Development of life prediction capabilities for liquid propellant rocket engines. Post-fire diagnostic system for the SSME system architecture study

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    This system architecture task (1) analyzed the current process used to make an assessment of engine and component health after each test or flight firing of an SSME, (2) developed an approach and a specific set of objectives and requirements for automated diagnostics during post fire health assessment, and (3) listed and described the software applications required to implement this system. The diagnostic system described is a distributed system with a database management system to store diagnostic information and test data, a CAE package for visual data analysis and preparation of plots of hot-fire data, a set of procedural applications for routine anomaly detection, and an expert system for the advanced anomaly detection and evaluation

    Hydrological and environmental issues of inter-basin water transfers in India: a case study of the Krishna River Basin

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    River basin managementRiver basin developmentDevelopment projectsWater transferFlowWater availabilitySurface waterWater balanceEnvironmental effectsErosionCoasts

    Comparative study of heat rejection systems for portable life support equipment Final report

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    Comparsion of heat rejection systems for portable life support equipment for earth orbital or lunar surface EV

    Sustainable development : fourth annual assessment of progress by the Scottish Government

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    SDC Scotland’s annual assessment is based on a review of government policy across a range of topics from economy and energy to education, health, waste and biodiversity. The conclusions and recommendations are also based on discussions with expert groups in each policy area, government civil servants and a stakeholder survey.Publisher PD

    Modelling understorey dynamics in temperate forests under global change : challenges and perspectives

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    The understorey harbours a substantial part of vascular plant diversity in temperate forests and plays an important functional role, affecting ecosystem processes such as nutrient cycling and overstorey regeneration. Global change, however, is putting these understorey communities on trajectories of change, potentially altering and reducing their functioning in the future. Developing mitigation strategies to safeguard the diversity and functioning of temperate forests in the future is challenging and requires improved predictive capacity. Process-based models that predict understorey community composition over time, based on first principles of ecology, have the potential to guide mitigation endeavours but such approaches are rare. Here, we review fourteen understorey modelling approaches that have been proposed during the last three decades. We evaluate their inclusion of mechanisms that are required to predict the impact of global change on understorey communities. We conclude that none of the currently existing models fully accounts for all processes that we deem important based on empirical and experimental evidence. Based on this review, we contend new models are needed to project the complex impacts of global change on forest understoreys. Plant functional traits should be central to such future model developments, as they drive community assembly processes and provide valuable information on the functioning of the understorey. Given the important role of the overstorey, a coupling of understorey models to overstorey models will be essential to predict the impact of global change on understorey composition and structure, and how it will affect the functioning of temperate forests in the future
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