53 research outputs found

    How Wood Fuels\u2019 Quality Relates to the Standards: A Class-Modelling Approach

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    The quality requirements of wood biofuels are regulated by a series of harmonized international standards. These standards define the technical parameter limits that influence the quality of solid biomass as a fuel. In 2014 the European reference standard for solid biofuel was replaced by the International ISO standard. In the case of wood chips, the main difference between the European and International standards is the definition of particle size distribution classes. In this context, this study analyses the quality of wood chips and its variation over the years according to the \u201cformer\u201d (EN 14691-4) and \u201cin force\u201d (ISO 17225-4) standards. A Soft Independent Modelling of Class Analogy (SIMCA) model was built to predict the best quality of wood chips and to clarify the relationship between quality and standard parameters, time and changes in the standard regulations. The results show that, compared to the EN standards, classification with the ISO standards increases the samples belonging to the best quality classes and decreases the not classified samples. Furthermore, all the SIMCA models have a high sensitivity (>90%), reflect the differences introduced to the quality standards and are therefore suitable for monitoring the quality of wood chips and their changes

    Productivity Analysis of an Un-Guyed Integrated Yarder-Processor with Running Skyline

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    An excavator-based integrated yarder-processor was evaluated in a clearfelling in centralNorway. The machine is unique because, as it uses a running skyline setup, yarding and processing cannot take place simultaneously as is the case with many European integrated tower yarders. Felling productivity was 10.6 m3 E15h-1, yarding 9.2 m3 E15h-1 and processing 10.9 m3 E15h-1. Given that yarding and processing take place alternately accounting for 54%and 46% of a system hour, the overall system productivity was 4.9 m3 E15h-1 (processed and stacked). The processing rate was approximately 30% of what is achieved by single grip harvesters, indicating the effect of space limitations, a possible over-dimensioned processing head, and the need to simplify the assortment list under such conditions. An increase in processing productivity would require a second feller-chokersetter in the crew, although neither would then be used to full capacity. Un-choking alone accounted for 19% of the yarding cycle timeand might be reduced by applying self-releasing chokers. System productivity needs to beincreased by 30–50% to make it competitive. Much of this could be achieved simply by deploying the machine in stands with larger mean tree volumes than those observed (0.27 m3)

    Quantitative and qualitative workload assessment in steep terrain forest operations: fostering a safer work environment through yarder automation

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    Many forestry roles have changed from being manual tasks with a high physical workload to being a machine operator task with a high mental workload. Automation can support a decrease in mental fatigue by removing tasks that are repetitive and monotonous for the operators. Cable yarding presents an ideal opportunity for early adoption of automation technology; specifically the carriage movement along a defined corridor. A Valentini V-850 cable yarder was used in an Italian harvesting setting, in order to gauge the ergonomic benefit of carriage control automation. The study showed that automating yarder carriage movements improved the ergonomic situation of the workers directly involved in the related primary tasks. However, the caveat is that improving one work task may negatively affect the other work tasks, and therefore introducing automation to a worksite must be done after considering all impacts on the whole system. Practitioner summary: Automation decreased the winch operator’s mental workload while improving overall productivity. At the same time, the mental and physiological workload of the operator tasked with bucking were slightly increased. Ideally, winch automation should be coupled with bucking mechanisation to balance the intervention and boost both operator well-being and productivity.publishedVersio

    Forest Workers and Steep Terrain Winching: the Impact of Environmental and Anthropometric Parameters on Performance

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    Winching is common in small-scale forest operations, especially on steep slopes, where tractors cannot reach the logs inside the forest. In this case, logs are dragged to the roadside with tractor-mounted winches, for later collection by transportation units. Winching is a heavy task, posing a high physiological stress on winching crew members. The aim of this study was to investigate the relationship between experienced workload, work conditions and operator fitness. The study confirmed the assumption that fit, young operators experience a lower workload than older ones. Workload depends on winching direction, and it is higher when winching downhill than when winching uphill. Results confirmed that gravity is the main factor, and it has a stronger effect than task type and tool weight. Walking uphill with no tools is heavier than walking downhill and carrying a steel cable. As a consequence, tool weight reduction can only palliate the problem, without solving it. Winching crews should be composed of fit, young workers. When the task is assigned to older workers, it is necessary to allow longer rest breaks, accepting a lower productivity

    Productivity Analysis of an Un-Guyed Integrated Yarder-Processor with Running Skyline

    Get PDF
    An excavator-based integrated yarder-processor was evaluated in a clearfelling in centralNorway. The machine is unique because, as it uses a running skyline setup, yarding and processing cannot take place simultaneously as is the case with many European integrated tower yarders. Felling productivity was 10.6 m3 E15h-1, yarding 9.2 m3 E15h-1 and processing 10.9 m3 E15h-1. Given that yarding and processing take place alternately accounting for 54%and 46% of a system hour, the overall system productivity was 4.9 m3 E15h-1 (processed and stacked). The processing rate was approximately 30% of what is achieved by single grip harvesters, indicating the effect of space limitations, a possible over-dimensioned processing head, and the need to simplify the assortment list under such conditions. An increase in processing productivity would require a second feller-chokersetter in the crew, although neither would then be used to full capacity. Un-choking alone accounted for 19% of the yarding cycle timeand might be reduced by applying self-releasing chokers. System productivity needs to beincreased by 30–50% to make it competitive. Much of this could be achieved simply by deploying the machine in stands with larger mean tree volumes than those observed (0.27 m3)

    Modelling Technical Efficiency of Horticulture Farming in Kosovo: An Application of Data Envelopment Analysis

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    With a view to integration into the European Union, the efficiency and competitiveness of the Kosovo' different sectors (including agriculture) must be improved. This paper assesses the technical efficiency (TE) of horticultural farms through Data Envelopment Analysis (DEA) applying output orientation. It was found that the TE of these farms is positively affected by their size, with large-size farms presenting overall higher technical efficiency. The research findings indicate that the degree of agricultural education does not have a significant impact on TE, whereas public assistance through subsidies and grants has a substantial and negative impact on TE, as confirmed by statistical analysis

    Development of a Novel Framework for the Assessment and Improvement of Climate Adaptation and Mitigation Actions in Europe

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    The greenhouse gases (GHG) emissions in the European Union (EU) are mainly caused by human activity from five sectors—power, industry, transport, buildings, and agriculture. To tackle all these challenges, the EU actions and policies have been encouraging initiatives focusing on a holistic approach but these initiatives are not enough coordinated and connected to reach the much needed impact. To strengthen the important role of regions in climate actions, and stimulate wide stakeholders’ engagement including citizens, a conceptual framework for enabling rapid and far-reaching climate actions through multi-sectoral regional adaptation pathways is hereby developed. The target audience for this framework is composed by regional policy makers, developers and fellow scientists. The scale of the framework emphasizes the regional function as an important meeting point and delivery arena for European and national climate strategies and objectives both at urban and rural level. The framework is based on transformative and no-regret measures, prioritizing the Key Community Systems (KCS) that most urgently need to be protected from climate impacts and risks.publishedVersio

    Hvordan implementere rÄdgivning som en mer naturlig og stÞrre del av regnskapstjenesten KL Regnskap Rosten tilbyr?

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    Vi har valgt Ä skrive oppgave om KL regnskap avdeling Rosten. KL regnskap er en kjede regnskapskontor med flere avdelinger i TrondheimsomrÄdet. Problemet til KL Rosten har vÊrt knyttet til det Ä Þke omsetningen pÄ rÄdgivning. Vi har i oppgaven vÄr sett pÄ hvordan KL skal klare Ä Þke omsetningen og utvikle rÄdgivningstjenesten. Dette har bunnet ut i problemstillingen: Hvordan implementere rÄdgivning som en stÞrre og mer naturlig og stÞrre del av regnskapstjenesten KL Regnskap Rosten tilbyr? For Ä kunne komme med gode anbefalinger og gi oppgaven tyngde, har vi fordypet oss i teori innen; konsulentvirksomhet, strategi, innovasjon, organisasjonsteori, GAP modellen, «blueprinting» og forskningsrapporter innen regnskapsbransjen. Gjennom metodedelen utformet vi en kvantitativ spÞrreundersÞkelse som vi sendte ut til KLs kunder. Vi Þnsket Ä undersÞke hvilke faktorer som var avgjÞrende for valg av regnskapskontor, hva de brukte KL til og behovet for rÄdgivning. Til slutt sÄ vi pÄ om kundene oppfattet KL i henhold til deres verdier. Vi merket fort at det ikke var lett Ä fÄ kundene til Ä svare pÄ undersÞkelsen, men etter en del purringer oppnÄdde vi til slutt en svarprosent pÄ drÞye femti prosent. Vi mener dette gir en indikasjon pÄ at dialogen KL har med kundene sine er for dÄrlig. PÄ bakgrunn av den lave svarprosenten valgte vi Ä gjennomfÞre kvalitative intervju med ansatte og kunder av KL. I tillegg hadde vi tre intervjuer med personer i tilknytning til bransjen, representert ved bank og skatteetaten. Resultatene fra undersÞkelsen viser at pris ikke er en avgjÞrende faktor. Kundene verdsetter kompetanse og kvalitet hÞyest ved valg av regnskapsbyrÄ. Vi ser ogsÄ et marked for tilleggstjenester som omhandler rÄdgivning. Kundene forbinder KL med fÞlgende av deres eksisterende verdier; positive, ordentlige og stabile. KL leverer regnskapstjenester til rett tid og samarbeider for kundens beste. Kunden oppfatter ikke at KL har blikk for nye lÞsninger og at de fÞrer til stÞrre lÞnnsomhet for kunden. Gjennom intervjuene fÄr vi en oppfatning av at regnskapsbransjen blir sett pÄ som lite innovativ. Alle intervjuene er klare pÄ at regnskapsbyrÄene har en god mulighet til Ä bli rÄdgivere. Banksjefene er ogsÄ klare pÄ at bank, revisjon og regnskapsbyrÄer vil konkurrere om de samme kundene i framtiden. Det pÄpekes at bank og revisjonsbransjen kan tilby rÄdgivningspakker, hvor kunden kan fÄ regnskapet med pÄ kjÞpet. Dette vil fÞre til store utfordringer for regnskapsbransjen. I intervjuene kom det fram at Ä definere rÄdgivning ikke er enkelt. Vi fikk mange ulike definisjoner som tyder pÄ at rÄdgivningsbegrepet er omfattende og diffust. Dette gjÞr det vanskelig Ä selge rÄdgivning som et eget produkt. VÄr anbefaling til KL ligger i det Ä designe et nytt konsept. Vi mener bÄde prissystemet og mÄten KL tilbyr rÄdgivning pÄ mÄ omgjÞres. Vi har i oppgaven designet et system hvor rÄdgivning er en del av regnskapstjenesten KL tilbyr. RÄdgivning utover dette blir en spesifisert tilleggstjeneste. Videre har vi kommet med forslag til hvordan KL kan organisere seg og sett pÄ om de har den nÞdvendige kompetansen som trengs. Som oppsummering kan vi konkludere med at KL ikke blir oppfattet som rÄdgivere og at de mÄ utforme et konsept om de skal klare Ä fÄ rÄdgivning til Ä bli en stÞrre og mer naturlig del av KL. Den generelle kompetansen mener vi er til stede, men de mÄ utvikle seg og tilegne seg kunnskap innenfor salg og hvordan opptre som konsulenter

    Fallgruver i byggeprosjekter

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    Denne rapporten tar utgangspunkt i bruprosjektet Tverrforbindelsen for Ä illustrere hvilke fallgruver det er vanlig Ä mÞte pÄ og hvordan disse kan hÄndteres pÄ en god mÄte. Tverrforbindelsen ble planlagt og bygget i Ärene 2010-2012. For Ä avgrense besvarelsen har vi mÄttet spisse problemstillingen, og endte opp med denne avgrensede problemstillingen: «Hvordan har Reinertsen hÄndtert de viktigste fallgruvene i prosjektet Tverrforbindelsen?» Det ble foretatt en litteraturstudie, for Ä finne ut hva som er kjent rundt den avgrensede problemstillingen. Erfaringene fra dette studiet ble grunnlaget for intervjuene. Det ble samlet inn bÄde primÊrdata og sekundÊrdata Oppgaven er bygget pÄ Andersen, Grude og Haugs (2012) fallgruver knyttet opp til styringsslÞyfen som er beskrevet i boken til Westhagen et al (2008). Der vi tar for oss noen utvalgte fallgruver under hvert punkt i styringsslÞyfen. Vi valgte ogsÄ Ä trekke ut organiseringen som et eget punkt i styringsslÞyfen slik som Westhagen et al (2006) beskriver i sin bok at dette er hjertet i styringsslÞyfen. Bacheloroppgaven vÄr er inndelt i 7 hovedkapitler med underkapitler og avsnitt. Disse kapitlene inneholder, fra start til slutt, innledning, metoder og kilder, begrunnelse for valg av fallgruver, fallgruver i de ulike omrÄdene i et prosjekt, hvor det ble trukket inn relevant teori og fakta, og disse ble drÞftet opp mot hverandre og til slutt ble kapittelet avsluttet med en delkonklusjon. Videre er det kapitler som inneholder konklusjonen, litteraturlisten og til slutt vedlegg. I resultatet av drÞftingene i de forskjellige underkapitlene om fallgruvene, kom det frem at Reinertsen hadde flere utfordringer og fallgruver i prosjektet Tverrforbindelsen, som de mÄtte hÄndtere underveis i prosjektet, men disse ble hÄndtert pÄ en god mÄte
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