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| 3. |
- Elbornsson, Jonas, et al.
(author)
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Analysis of Mismatch Effects in Randomly Interleaved A/D Converter System
- 2005
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In: IEEE Transactions on Circuits And Systems Part I. - : Institute of Electrical and Electronics Engineers (IEEE). - 1057-7122 .- 1558-1268. ; 52:3, s. 465-476
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Journal article (peer-reviewed)abstract
- To significantly increase the sampling rate of an A/D converter (ADC), a time interleaved ADC system is a good option. The drawback of a time interleaved ADC system is that the ADCs are not exactly identical due to errors in the manufacturing process. This means that time, gain and offset mismatch errors are introduced in the ADC system. These errors cause non harmonic distortion in the sampled signal. One way to decrease the impact of the mismatch errors is to spread the distortion over a wider frequency range by randomizing the order in which the ADCs are used in the interleaved structure. In this paper we analyze how the spectrum is affected by mismatch errors in a randomly interleaved ADC system. We also discuss how the mismatch errors can be estimated.
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| 5. |
- Allerup, Jonas, et al.
(author)
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Snabbstatistik - preliminär skattning av utsläpp av växthusgaser 2015
- 2015
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Reports (other academic/artistic)abstract
- Naturvårdsverket har uppdragit åt SMED att utföra preliminära skattningar av utsläpp av växthusgaser 2014 för publicering i maj 2015. Med tanke på den korta tidsfristen och den i vissa fall begränsade tillgången till uppdaterade indata levereras skattningarna med en något annan sektorsindelning än till ordinarie rapportering. Utsläppen redovisas i kt CO2-ekvivalenter totalt samt per sektor enligt den modifierade sektorsindelningen. Metodiken baseras i huvudsak på SMED 2012 och 2006 års rapporterings- och metodriktlinjer från UNFCCC och IPCC. Förutsättningarna och metodvalet skiljer sig åt mellan olika sektorer. För utsläpp från energiproduktion och transporter samt i viss mån industriprocesser och avfallsförbränning har data avseende 2014 funnits tillgängliga och utnyttjats. Utsläpp från jordbruk och avfallshantering exklusive förbränning har skattats genom framskrivning av tidigare års utsläpp med linjär regression. Resultatet av beräkningarna visar att Sveriges totala utsläpp av växthusgaser 2014 var 53 888 kt CO2-ekvivalenter exklusive utrikes transporter. Det innebär en minskning med 3 procent jämfört med 2013 års utsläpp enligt Sveriges submission 2015. Totalt 82 procent av utsläppen har beräknats baserat på uppdaterade data avseende 2014. Resultatet är preliminärt och 2014 års utsläpp kommer att revideras till ordinarie submission 2016. Inga osäkerhetsskattningar har gjorts.Tidigare års preliminära uppskattningar av utsläppen har legat cirka en procent lägre än det slutgiltiga resultatet för aktuell submission. Detta kan ge en grov fingervisning om den förväntade avvikelsen från den slutgiltiga skattningen.
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| 6. |
- Allerup, Jonas, et al.
(author)
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Utveckling av rapportering till CLRTAP NFR 1A och 5 map EMEP Guidebook 2013, steg 2
- 2015
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Reports (other academic/artistic)abstract
- Sverige rapporterar årligen emissioner till luft för uppföljning av Sveriges åtaganden gentemot de olika protokollen under FN:s Luftkonvention (UNECE CLRTAP) samt EU:s Takdirektiv (NEC). Vid ett flertal tillfällen har det framkommit att Sveriges inventering av luftföroreningar är ofullständig och alltså saknar utsläpp från vissa källor och av vissa ämnen. Det innebär bland annat att beräknade nationella totaler troligtvis är underskattade, vilket försvårar arbetet med att följa upp de olika åtagandena. I den senaste ERT-granskarrapporten rekommenderas att Sverige förbättrar fullständigheten av sin rapportering, och det påpekas att detta kan ske genom att applicera default-faktorer från EMEP/EEA Guidebook 2013. I de fall där det finns default-metoder och default-emissionsfaktorer tillgängliga i EMEP/EEA Guidebook 2013 för koderna NFR 1A och NFR 5 (A, B1, B2, D1, D2, D3, E) och Sverige har rapporterat ”NE” (Not estimated) eller ”NA” (Not applicable), har vi i denna studie gjort beräkningar genom att applicera default-emissionsfaktorn på aktivitetsdata. För avfallssektorn har en del ny aktivitetsdata implementerats för att matcha default emissionsfaktorer från Guidebook. De beräknade emissionerna står endast för en liten del av den nationella totalen för respektive ämne som rapporteras till submission 2015 och de nya beräkningarna kommer att implementeras i inventeringen.
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| 7. |
- Ammenberg, Jonas, et al.
(author)
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Biogas Research Center, BRC : Slutrapport för etapp 1
- 2015
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Reports (other academic/artistic)abstract
- Biogas Research Center (BRC) är ett kompetenscentrum för biogasforskning som finansieras av Energimyndigheten, LiU och ett flertal externa organisationer med en tredjedel vardera. BRC har en mycket bred tvärvetenskaplig inriktning och sammanför biogasrelaterad kompetens från flera olika områden för att skapa interaktion på flera olika plan:mellan näringsliv, akademi och samhälle,mellan olika perspektiv, samtmellan olika discipliner och kompetensområden.BRC:s vision är:Resurseffektiva biogaslösningar finns genomförda i många nya tillämpningar och bidrar till en mer hållbar energiförsörjning, förbättrat miljötillstånd och goda affärer.BRC:s särskilda roll för att uppnå denna vision är att bidra med kunskapsförsörjning och process-/teknikutveckling för att facilitera utveckling, innovation och implementering av biogaslösningar. Resurseffektivitet är ett nyckelord, vilket handlar om att förbättra befintliga processer och system samt utveckla biogaslösningar i nya sektorer och möjliggöra användning av nya substrat.For BRC:s etapp 1, den första tvåårsperioden mellan 2012-2014, var forskningsprojekten organiserade enligt tabellen nedan. Den visar viktiga utmaningar för biogasproducenter och andra intressenter, samt hur dessa ”angreps” med åtta forskningsprojekt. Fem av projekten var av explorativ karaktär i bemärkelsen att de var bredare och mer framtidsorienterade - exempelvis utvärderade flera möjliga tekniska utvecklingsmöjligheter (EP1-5). Tre projekt hade ett tydligare fokus på teknik- och processutveckling (DP6-8).I den här slutrapporten ges en kortfattad bakgrundsbeskrivning och det finns en introduktion till vad den här typen av kompetenscentrum innebär generellt. Därefter finns mer detaljerad information om BRC, exempelvis gäller det centrumets etablering, relevans, vision, hörnstenar och utveckling. De deltagande organisationerna presenteras, både forskargrupperna vid Linköpings universitet och partners och medlemmar. Vidare finns en mer utförlig introduktion till och beskrivning av utmaningarna i tabellen och kortfattat information om forskningsprojekten, följt av ett kapitel som berör måluppfyllelse och den externa utvärdering som gjorts av BRC:s verksamhet. Detaljerad, listad information finns till stor del i bilagorna.Kortfattat kan det konstateras att måluppfyllelsen överlag är god. Det är speciellt positivt att så många vetenskapliga artiklar publicerats (eller är på gång att publiceras) kopplat till forskningsprojekten och även i det vidare centrumperspektivet. Helt klart förekommer en omfattande verksamhet inom och kopplat till BRC. I etapp 2 är det viktigt att öka andelen mycket nöjda partner och medlemmar, där nu hälften är nöjda och hälften mycket nöjda. Det handlar framför allt om stärkt kommunikation, interaktion och projektledning. Under 2015 förväntas åtminstone två doktorsexamina, där avhandlingarna har stor koppling till forskningen inom etapp 1.I början på år 2014 skedde en extern utvärdering av verksamheten vid BRC med huvudsyftet att bedöma hur väl centrumet lyckats med etableringen samt att granska om det fanns förutsättningar för framtida framgångsrik verksamhet. Generellt var utfallet mycket positivt och utvärderarna konstaterade att BRC på kort tid lyckats etablera en verksamhet som fungerar väl och engagerar det stora flertalet deltagande aktörer, inom relevanta områden och där de flesta involverade ser BRC som en befogad och väl fungerande satsning, som de har för avsikt att även fortsättningsvis stödja. Utvärderingen bidrog också med flera relevant tips och till att belysa utmaningar.Utöver denna slutrapport finns separata publikationer från forskningsprojekten.Arbetet som presenteras i rapporten har finansierats av Energimyndigheten och de medverkande organisationerna.
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| 8. |
- Ammenberg, Jonas, et al.
(author)
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Improving the CO2 performance of cement, part III : The relevance of industrial symbiosis and how to measure its impact
- 2015
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In: Journal of Cleaner Production. - : Elsevier. - 0959-6526 .- 1879-1786. ; 98, s. 145-155
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Journal article (peer-reviewed)abstract
- Cement production contributes to extensive CO2 emissions. However, the climate impact can vary significantly between different production systems and different types of cement products. The market is dominated by ordinary Portland cement, which is based on primary raw materials and commonly associated with combustion of vast amounts of fossil fuels. Therefore, the production of Portland cement can be described as a rather linear process. But there are alternative options, for example, involving large amounts of industrial byproducts and renewable energy which are more cyclic and thus can be characterized as relatively “synergistic”.The main purpose of this article is to study how relevant the leading ideas of industrial symbiosis are for the cement industry based on a quantitative comparison of the CO2 emissions from different cement production systems and products, both existing and hypothetical. This has been done by studying a group of three cement plants in Germany, denoted as ClusterWest, and the production of cement clinker and three selected cement products. Based on this analysis and literature, it is discussed to what extent industrial symbiosis options can lead to reduced CO2 emissions, for Cluster West and the cement industry in general.Utilizing a simplified LCA model (“cradle to gate”), it was shown that the CO2 emissions from Cluster West declined by 45% over the period 1997e2009, per tonne of average cement. This was mainly due to a large share of blended cement, i.e., incorporation of byproducts from local industries as supplementary cementitious materials. For producers of Portland cement to radically reduce the climate impact it is necessary to engage with new actors and find fruitful cooperation regarding byproducts, renewable energy and waste heat. Such a development is very much in line with the key ideas of industrial ecology and industrial symbiosis, meaning that it appears highly relevant for the cement industry to move further in this direction. From a climate perspective, it is essential that actors influencing the cement market acknowledge the big difference between different types of cement, where an enlarged share of blended cement products (substituting clinker with byproducts such as slag and fly ash) offers a great scope for future reduction of CO2 emissions.
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| 9. |
- Ammenberg, Jonas, 1973-, et al.
(author)
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Industrial symbiosis for improving the CO2-performance of cement
- 2012
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Conference paper (peer-reviewed)abstract
- Justification of the paper Cement production is one of the largest contributors to global CO2-emissions. However, the context and characteristics of the production and the cement products vary a lot. A significant part of the production must be characterized as rather linear, for example, to a large extent based on fossil fuels and involving material flows that are not closed. But there are also much more synergistic examples, involving industrial by-products, renewable energy, etc. Clearly, there are opportunities for improvement within the cement industry and it is interesting to analyze to what extent increased industrial symbiosis can lead to improved climate performance. This has been done by studying the production of cement clinker and three selected cement products produced within the Cluster West in Germany, consisting of three cement plants that are owned by the multinational company CEMEX. The methodology is mostly based on Life Cycle Assessment (LCA), from cradle-to-gate.PurposeThe overall purpose is to contribute to a better understanding of the climate performance of different ways of producing cement, and different cement products. The climate impact is assessed for “traditional”, rather linear, ways of making cement, but also two more synergistic alternatives, where the by-product granulated blast furnace slag (GBFS) is utilized to a large extent, substituting cement clinker. It is also shown how the climate performance of the West Cluster has changed from 1997 until 2009 (the main year of study), and investigated how further industrial symbiosis measures could improve the performance.Theoretical frameworkTo a large extent this project has been based on mapping and analysis of relevant flows of material and energy, where LCA methodology has played an important part. Theoretical and methodological aspects related to the fields of Industrial Ecology and Industrial Symbiosis have played an important role. The findings are discussed in relation to some of the key ideas within these fields. The paper generates insight into the methodological challenge of quantifying environmental performance of different production approaches and basically what CO2 improvement potential cement industry has by taking industrial symbiosis measures.ResultsThe results showed that the cement clinker produced at Cluster West is competitive from a climate perspective, causing CO2-eq missions that are a couple of percent lower than the world average. During the twelve year period from 1997 to 2009 these emissions became about 12 percent lower, which was mainly achieved by production efficiency measures but also via changing fuels. However, the most interesting results concern the blended cement products. It was manifested that it is very advantageous from a climate perspective to substitute clinker with granulated blast furnace slag. For example, the CO2-eq emissions were estimated to be 65 percent lower for the best product compared to “ordinary cement”.ConclusionsInformation and measures at the plant level are not sufficient to compare products or to significantly reduce the climate impact related to cement. To achieve important reductions of the emissions, measures and knowledge at a higher industrial symbiosis level are needed.
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| 10. |
- Ammenberg, Jonas, 1973-, et al.
(author)
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Industrial symbiosis for improving the CO2-performance of cement production : Final report of the CEMEX-Linköping University industrial ecology project, 2011
- 2011
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Reports (other academic/artistic)abstract
- This report contains information about a research project lead by researchers from Environmental Technology and Management at Linköping University in Sweden. It has been conducted in cooperation with staff from the global cement company CEMEX. The study has been focused on three cement plants in the western parts of Germany, referred to as CEMEX Cluster West. They form a kind of work alliance, together producing several intermediate products and final products. One of the plants is a cement plant with a kiln, while the other two can be described as grinding and mixing stations. The overall aim has been to contribute to a better understanding of the climate performance of different ways of producing cement, and different cement products. An important objective was to systematically assess different cement sites, and production approaches, from a climate perspective, thereby making it easier for the company to analyze different options for improvements. Theoretical and methodological aspects related to the fields of Industrial Ecology (IE) and Industrial Symbiosis (IS) have played an important role. A common way of making cement is to burn limestone in a cement kiln. This leads to the formation of cement clinker, which is then grinded and composes the main component of Ordinary Portland Cement. One very important phase of the production of clinker is the process of calcination, which takes place in the kiln. In this chemical reaction calcium carbonate decomposes at high temperature and calcium oxide and carbon dioxide are produced. The calcination is of high importance since it implies that carbon bound in minerals is transformed to CO2. A large portion of the CO2 emissions related to clinker production is coming from the calcination process. Both clinker and Ordinary Portland Cement (CEM I 42.5) were studied. However, there are other ways of making cement, where the clinker can be substituted by other materials. Within Cluster West, granulated blast furnace slag from the iron and steel industry is used to a large extent as such a clinker substitute. This slag needs to be grinded, but an important difference compared to clinker is that it has already been treated thermally (during iron production) and therefore does not have to be burned in a kiln. With the purpose to include products with clearly different share of clinker substitutes, the project also comprised CEM III/A 42.5 (blended cement, about 50% clinker) and CEM III/B 42.5 N-. (blended cement, about 27% clinker). To sum up, this means that the study involved “traditional”, rather linear, ways of making cement, but also two more synergistic alternatives, where a byproduct is utilized to a large extent instead of clinker. The methodology is mostly based on Life Lycle Assessment (LCA), from cradle-to-gate, using the SimaPro software. This means that the cement products have been studied from the extraction of raw materials until they were ready for delivery at the “gate” of Cluster West. The functional unit was 1 tonne of product. A lot of data was collected regarding flows of material and energy for the year of 2009. In addition, some information concerning 1997 was also acquired. Most of the used data has been provided by CEMEX, but to be able to cover upstream parts of the life cycle data from the Ecoinvent database has also been utilized. The extensive data concerning 2009 formed the base for the project and made it possible to study the selected products thoroughly for this year. However, the intention was also to assess other versions of the product system – Cluster West in 1997 and also a possible, improved future case. For this purpose, a conceptual LCA method was developed that made it possible to consider different products as well as different conditions for the product system. Having conducted the baseline LCA, important results could be generated based on knowledge about six key performance indicators (KPIs) regarding overall information about materials, the fuel mix and the electricity mix. The conceptual LCA method could be used for other products and versions of Cluster West, without collecting large amounts of additional specific Life Cycle Inventory (LCI) data. The developed conceptual LCA method really simplified the rather complex Cluster West production system. Instead of having to consider hundreds of parameters, the information about the six KPIs was sufficient to estimate the emissions from different products produced in different versions of the production system (Cluster West). The results showed that the clinker produced at Cluster West is competitive from a climate perspective, causing CO2-eq missions that are a couple of percent lower than the world average. During the twelve year period from 1997 to 2009 these emissions became about 12 percent lower, which was mainly achieved by production efficiency measures but also via changing fuels. However, the most interesting results concern the blended cement products. It was manifested that it is very advantageous from a climate perspective to substitute clinker with granulated blast furnace slag, mainly since it reduces the emissions accounted related to calcination. For example, the CO2-eq emissions related to CEM III/B product were estimated to be 65 percent lower than those for CEM I. A framework for identifying and evaluating options for improvement has been developed and applied. Based on that framework the present production system was analyzed and illustrated, and different measures for reducing the climate impact were shown and evaluated. Two possible scenarios were defined and the conceptual LCA model used to estimate their climate performance. The authors’ recommendation is for CEMEX to continue to increase the share of CEM III (the share of good clinker substitutes), and to make efforts to shift the focus on the market from clinker and cement plants to different types of cement (or concrete) or even better to focus on the lifecycle of the final products such as buildings and constructions. Information and measures at the plant level are not sufficient to compare products or to significantly reduce the climate impact related to cement. To achieve important reductions of the emissions, measures and knowledge at a higher industrial symbiosis level are needed.
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