| 1. |
- Kerzenmacher, T., et al.
(författare)
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Validation of NO2 and NO from the Atmospheric Chemistry Experiment (ACE)
- 2008
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Ingår i: Atmospheric Chemistry and Physics. - : Copernicus GmbH. - 1680-7316 .- 1680-7324. ; 8:19, s. 5801--5841-
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Tidskriftsartikel (refereegranskat)abstract
- Vertical profiles of NO2 and NO have been obtained from solar occultation measurements by the Atmospheric Chemistry Experiment (ACE), using an infrared Fourier Transform Spectrometer (ACE-FTS) and (for NO2) an ultraviolet-visible-near-infrared spectrometer, MAESTRO (Measurement of Aerosol Extinction in the Stratosphere and Troposphere Retrieved by Occultation). In this paper, the quality of the ACE-FTS version 2.2 NO2 and NO and the MAESTRO version 1.2 NO2 data are assessed using other solar occultation measurements (HALOE, SAGE II, SAGE III, POAM III, SCIAMACHY), stellar occultation measurements (GOMOS), limb measurements (MIPAS, OSIRIS), nadir measurements (SCIAMACHY), balloon-borne measurements (SPIRALE, SAOZ) and ground-based measurements (UV-VIS, FTIR). Time differences between the comparison measurements were reduced using either a tight coincidence criterion, or where possible, chemical box models. ACE-FTS NO2 and NO and the MAESTRO NO2 are generally consistent with the correlative data. The ACE-FTS and MAESTRO NO2 volume mixing ratio (VMR) profiles agree with the profiles from other satellite data sets to within about 20% between 25 and 40 km, with the exception of MIPAS ESA (for ACE-FTS) and SAGE II (for ACE-FTS (sunrise) and MAESTRO) and suggest a negative bias between 23 and 40 km of about 10%. MAESTRO reports larger VMR values than the ACE-FTS. In comparisons with HALOE, ACE-FTS NO VMRs typically (on average) agree to ±8% from 22 to 64 km and to +10% from 93 to 105 km, with maxima of 21% and 36%, respectively. Partial column comparisons for NO2 show that there is quite good agreement between the ACE instruments and the FTIRs, with a mean difference of +7.3% for ACE-FTS and +12.8% for MAESTRO.
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| 2. |
- Folkesson, Klas, 1976
(författare)
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Model-Based Stem Volume Retrieval and Windthrow Detection using CARABAS and P-band SAR
- 2008
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Radar remote sensing is an efficient method for monitoring forests over large areas. Radar waves transmitted from a system carried by a satellite or an aircraft interact with trees on the ground, and the reflected waves are used to form images which are independent of weather and light conditions. Information in the images is then used to retrieve forest parameters.CARABAS is an airborne synthetic aperture radar (SAR) system. Due to the long wavelengths of the system (3-15 m), the radar signal is able to penetrate the forest canopies and for boreal forests the main backscattering component is the ground-trunk double-bounce. The scattering strength is directly related to the stem volume and hence stem volume retrieval with CARABAS has higher accuracy than SAR systems using shorter wavelengths. However, the ground-trunk double-bounce is very sensitive to ground slope and if not corrected for, ground slope will cause the stem volume to be underestimated.By using multiple images acquired with different flight headings and combining the image information with ground topography data in a model-based inversion method, most of the ground topography influence on the retrieved stem volume is removed. With four CARABAS images and a coarse digital elevation model with 50 m horizontal grid, the stem volume can be retrieved with a root mean square error(RMSE) of 48 m3/ha for stem volumes in the range 80-700 m3/ha. The proposed retrieval method gives better accuracy and is more robust than existing heuristic methods. By using this method, the retrieval accuracy in areas with ground topography is similar to that of similar forests standing on flat and horizontal ground.Another forestry application where CARABAS and other airborne SAR systems with long-wavelengths and high resolution can provide timely and useful information is in the detection of windthrown trees. A method for detecting windthrows in CARABAS images and a discussion about when windthrows can be detected is presented in this thesis.
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| 3. |
- Lodén, Jonas, 1973, et al.
(författare)
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Towards Energy Efficient Housing – the importance of local energy planning
- 2009
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Ingår i: Proceedings of International Forum on Energy Efficiency in Housing, 23-25 November 2009, Vienna, Austria.
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Konferensbidrag (refereegranskat)abstract
- A strategy for local energy planning must be in place in order to transform the local energy system and must comprise all relevant sectors and decision makers, i.e. include the residential sector with its relevant stakeholders. Thus, the housing sector cannot be treated inisolation but should rather be part of an analysis which takes a municipal energy systems perspective. This paper reports from an EU IEE (Intelligent Energy Europe) supported work named PATH-TO-RES which develops a methodology to be used as support tool for local energyplanning. The work uses a number of local case studies (Göteborg (SE), Valencia (ES), Dunkerque (FR), Gdansk (PL) and Arnhem and Lochem (NL)) to develop a step-by-stepassessment which can evaluate and define Pathways to renewable and efficient energy systems.A Pathway is a cost efficient way to bridge over from the present energy system to a sustainable system. In short, the proposed methodology starts with a detailed description of the present system (energy infrastructure as well as decision makers and stakeholders) and, based on this, anumber of steps are defined with the aim to serve as check points to ensure that one or more Pathways can be formulated which describe how the local energy system can be transformed to comply with goals and targets.In order to describe the energy systems of the six case studies in a common way, a schematic model called a RES-diagram (RES=Reference Energy System) has been applied, from which the structure (i.e. components, flows and connections) and energy balance of the systems can bedetermined. In the six municipalities studied considerable variation of population, land area and scale and characteristics of the existing energy systems exist. Differences and similarities between the six systems are highlighted and the paper discusses pre-requisites and conditions for municipal energy planning, based on energy systems of the case study regions.
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| 4. |
- Schidler, S, et al.
(författare)
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Performance Targets in Production Processes (PT-PRO) - final report
- 2007
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- One of the main actions of the European Environmental Technologies Action Plan (ETAP) is: "Setting ambitious targets to improve the environmental performance of technologies within a given timeframe. This should encourage technological development while preparing the markets to accept and prepare for these high standard environmental technologies". On request of DG Environment, the JRC-IPTS launched a project on Performance Targets for Industry Processes (PT-PRO project), with the objective to further define concepts and to identify the conditions necessary to implement the concept of Performance Targets. The project was carried out with the help of ITA, ÖAW, GMV/IVL, FEA and TNO. This report provides a definition of the main elements of Performance Targets and an overview of the general principles for their implementation. Based on four case study sectors (the iron & steel, cement, pulp & paper and the textile industries), an illustration of these different elements is provided in relation with a range of industry sectors and their environmental challenges, existing regulations, technical potentials, market situations and organisational structure. The report also discusses the best conditions and limitations of setting Performance Targets for the industry and the possible value-added.
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| 5. |
- Hansson, Julia, 1978, et al.
(författare)
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Co-firing biomass with coal for electricity generation—An assessment of the potential in EU27
- 2009
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Ingår i: Energy Policy. - : Elsevier BV. - 0301-4215. ; 37:4, s. 1444-1455
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Tidskriftsartikel (refereegranskat)abstract
- The European Union aims to increase bioenergy use. Co-firing biomass with coal represents an attractive near-term option for electricity generation from renewable energy sources (RES-E). This study assesses the near-term technical potential for biomass co-firing with coal in the existing coal-fired power plant infrastructure in the EU27 Member States. The total technical potential for RES-E frombiomass co-firing amounts to approximately 50–90 TWh/yr, which requires a biomass supply of approximately 500–900 PJ/yr. The estimated co-firing potential in EU27 amounts to 20–35% of the estimated gap between current RES-E production and the RES-E target for 2010. However, for some member states the national co-firing potential is large enough to fill the national gap. The national biomass supply potential is considerably larger than the estimated biomass demand for co-firing for all member states. About 45% of the estimated biomass demand for co-firing comes from plants located close to the sea or near main navigable rivers and indicates the possibility for biomass import by sea transport. Thus, biomass co-firing has the potential to contribute substantially to the RES-E development in EU27.
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| 6. |
- Rexfelt, Oskar, 1975
(författare)
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User-Centred Design and Technology-Mediated Services- Identifying and Addressing Challenges by Analysing Activities
- 2008
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- User-centred design has a focus on designing products to satisfy user needs rather than emanating from a technological starting point. Understanding user needs when developing products is considered a key component to achieve market success today.User-centred design is almost always described as a way to design products that satisfy user needs. While the word product does not necessarily exclude services, it is the design of tangible goods (or in some cases software solutions) that generally is the issue. However, most products which are sold today are in fact containing some kind of service. Furthermore, services that are sold often include ‘traditional’ technology necessary for delivering the services – technology which is becoming increasingly complex. In such services the users are often required to interact with this technology in order to realise the service. Two examples are bus journeys, where the users have to travel onboard the bus, and Internet information services, where the users have to interact with a website. These services are technology-mediated.The aim of this thesis was to explore how the user-centred design approach, normally used for designing tangible goods, can help in designing technology-mediated services. Three different research projects regarding technology-mediated services were studied. An activity-based framework was used to analyse, in retrospect, methods and outcomes of the three projects.Challenges for designing technology-mediated services that satisfy user needs were identified. These challenges were found to be a consequence of two important prerequisites of designing technology-mediating services: the intangible and complex characteristics of services, and the need for users to interact with technology.Technology-mediated services are special in relation to both tangible products and services. The main challenge lies in the fact that the two prerequisites must be considered concurrently. Today, user-centred design is not optimised to cope with this challenge. It needs to be complemented with new methods, but also new knowledge. The traditional methods in user-centred design can be useful, but the consequences of applying them to user-centred design instead of traditional products need to be understood. To achieve this understanding an activity-based approach to designing technology-mediated services is proposed. Within this thesis, three individually different areas related to technology-mediated services have been analysed on the basis of activity theoretical concepts. The potential of such an approach lies in its possibility to provide an organised and consistent way to investigate, describe, and understand technology-mediated services and how these affect people’s everyday activities.When technology-mediated services are designed it is the users’ experience of the complete solution, including the technology and the service content, which is to satisfy user needs. Considering the user-technology interaction alone is not enough.
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| 7. |
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| 8. |
- Berndes, Göran, 1966, et al.
(författare)
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Bioenergy expansion in the EU: Cost-effective climate change mitigation, employment creation and reduced dependency on imported fuels
- 2007
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Ingår i: Energy Policy. - : Elsevier BV. - 0301-4215. ; 35:12, s. 5965-5979
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Tidskriftsartikel (refereegranskat)abstract
- Presently, the European Union (EU) is promoting bioenergy. The aim of this paper is to study the prospects for using domestic biomass resources in Europe and specifically to investigate whether different policy objectives underlying the promotion of bioenergy (cost-effective climate change mitigation, employment creation and reduced dependency on imported fuels) agree on which bioenergy options that should be used. We model bioenergy use from a cost-effectiveness perspective with a linear regionalized energy- andtransport-system model and perform supplementary analysis. It is found that the different policy objectives do not agree on the order of priority among bioenergy options. Maximizing climate benefits cost-effectively is in conflict with maximizing employment creation. The former perspective proposes the use of lignocellulosic biomass in the stationary sector, while the latter requires biofuels for transport based on traditional agricultural crops. Further, from a security-of-supply perspective, the appeal of a given bioenergy option depends on how oil and gas import dependencies are weighed relative to each other. Consequently, there are tradeoffs that need to be addressed by policymakers promoting the use of bioenergy. Also, the importance of bioenergy in relation to employment creation and fuel import dependency reduction needs to be further addressed.
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| 10. |
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