896 resultados para Simulation Systems Analysis
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The past four decades have witnessed an explosive growth in the field of networkbased facilitylocation modeling. This is not at all surprising since location policy is one of the mostprofitable areas of applied systems analysis in regional science and ample theoretical andapplied challenges are offered. Location-allocation models seek the location of facilitiesand/or services (e.g., schools, hospitals, and warehouses) so as to optimize one or severalobjectives generally related to the efficiency of the system or to the allocation of resources.This paper concerns the location of facilities or services in discrete space or networks, thatare related to the public sector, such as emergency services (ambulances, fire stations, andpolice units), school systems and postal facilities. The paper is structured as follows: first,we will focus on public facility location models that use some type of coverage criterion,with special emphasis in emergency services. The second section will examine models based onthe P-Median problem and some of the issues faced by planners when implementing thisformulation in real world locational decisions. Finally, the last section will examine newtrends in public sector facility location modeling.
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We have recently shown that at isotopic steady state (13)C NMR can provide a direct measurement of glycogen concentration changes, but that the turnover of glycogen was not accessible with this protocol. The aim of the present study was to design, implement and apply a novel dual-tracer infusion protocol to simultaneously measure glycogen concentration and turnover. After reaching isotopic steady state for glycogen C1 using [1-(13)C] glucose administration, [1,6-(13)C(2)] glucose was infused such that isotopic steady state was maintained at the C1 position, but the C6 position reflected (13)C label incorporation. To overcome the large chemical shift displacement error between the C1 and C6 resonances of glycogen, we implemented 2D gradient based localization using the Fourier series window approach, in conjunction with time-domain analysis of the resulting FIDs using jMRUI. The glycogen concentration of 5.1 +/- 1.6 mM measured from the C1 position was in excellent agreement with concomitant biochemical determinations. Glycogen turnover measured from the rate of label incorporation into the C6 position of glycogen in the alpha-chloralose anesthetized rat was 0.7 micromol/g/h.
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The project "Quantification and qualification of ambulatory health care", financed by the Swiss National Science Foundation and covering the Cantons of Vaud and Fribourg, has two main goals: --a structural study of the elements of the ambulatory care sector. This is done through inventories of the professions concerned (physicians, public health nurses, physiotherapists, pharmacists, medical laboratories), allowing to better characterize the "offer". This inventory work includes the collect and analysis of existing statistical data as well as surveys, by questionnaires sent (from September 1980) to the different professions and by interviews. --a functional study, inspired from the US National Ambulatory Medical Care Survey and from similar studies elsewhere, in order to investigate the modes of practice of various providers, with particular regard to interprofessional collaboration (through studying referrals from the ones to the others). The first months of the project have been used for a methodological research in this regard, centered on the use of systems analysis, and for the elaboration of adequate instruments.
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Meesauuni on sulfaattiselluloosan valmistuksen kemikaalikierron apukemikaalin, kalkin valmistukseen käytettävä laite. Rakenteeltaan meesauuni koostuu pyöreästä lievästi horisontaalitasosta kaltevaan asentoon tuetusta putkesta sekä putkea tukevista kannatuselimistä. Meesauunia pyöritetään käytön aikana pituusakselinsa ympäri. Työn tarkoituksena oli rakentaa ADAMS-simulointiohjelmistoon käyttöliittymä meesauunin simulointimallin luomiseen uunin päämittojen avulla. Työssä selvitetään simulointimallin soveltuvuutta uunin kannatuselimiin kohdistuvien voimien tutkimiseen uunin normaaliajossa ja tietyissä ongelmatilanteissa. Työssä suoritettujen simulointien todettiin vastaavan melko hyvin todellista meesauunia ja tukevan ajatusta ADAMS:in käyttämisestä meesauunin mekaniikan simulointiin. Samalla todettiin kuitenkin lisämittausten kehittämisen tarpeellisuus ennen pidemmälle meneviä johtopäätöksiä.
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Diplomityön tavoitteena on kehittää Komartek Oyj:n kaukolämpöverkoston laskentaohjelmistoa. Tarkoituksena on kehittää laskentaohjelmiston nykyisiä ominaisuuksia sekä lisätä ohjelmistoon uusia ominaisuuksia. Diplomityön alussa tutustuttiin laskentaohjelmistoon ja sen toiminta raportointiin. Tämän jälkeen aloitettiin uusien ominaisuuksien määrittäminen ja lisääminen ohjelmistoon. Diplomityössä käsitellään kaukolämpöverkoston virtauslaskennan teoriaa yleisesti sekä kaukolämpöverkostossa olevien laskennallisten elementtien huomioiminen verkostolaskennnassa.
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Monte Carlo simulations were used to generate data for ABAB designs of different lengths. The points of change in phase are randomly determined before gathering behaviour measurements, which allows the use of a randomization test as an analytic technique. Data simulation and analysis can be based either on data-division-specific or on common distributions. Following one method or another affects the results obtained after the randomization test has been applied. Therefore, the goal of the study was to examine these effects in more detail. The discrepancies in these approaches are obvious when data with zero treatment effect are considered and such approaches have implications for statistical power studies. Data-division-specific distributions provide more detailed information about the performance of the statistical technique.
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The neural mechanisms determining the timing of even simple actions, such as when to walk or rest, are largely mysterious. One intriguing, but untested, hypothesis posits a role for ongoing activity fluctuations in neurons of central action selection circuits that drive animal behavior from moment to moment. To examine how fluctuating activity can contribute to action timing, we paired high-resolution measurements of freely walking Drosophila melanogaster with data-driven neural network modeling and dynamical systems analysis. We generated fluctuation-driven network models whose outputs-locomotor bouts-matched those measured from sensory-deprived Drosophila. From these models, we identified those that could also reproduce a second, unrelated dataset: the complex time-course of odor-evoked walking for genetically diverse Drosophila strains. Dynamical models that best reproduced both Drosophila basal and odor-evoked locomotor patterns exhibited specific characteristics. First, ongoing fluctuations were required. In a stochastic resonance-like manner, these fluctuations allowed neural activity to escape stable equilibria and to exceed a threshold for locomotion. Second, odor-induced shifts of equilibria in these models caused a depression in locomotor frequency following olfactory stimulation. Our models predict that activity fluctuations in action selection circuits cause behavioral output to more closely match sensory drive and may therefore enhance navigation in complex sensory environments. Together these data reveal how simple neural dynamics, when coupled with activity fluctuations, can give rise to complex patterns of animal behavior.
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NlmCategory="UNASSIGNED">A version of cascaded systems analysis was developed specifically with the aim of studying quantum noise propagation in x-ray detectors. Signal and quantum noise propagation was then modelled in four types of x-ray detectors used for digital mammography: four flat panel systems, one computed radiography and one slot-scan silicon wafer based photon counting device. As required inputs to the model, the two dimensional (2D) modulation transfer function (MTF), noise power spectra (NPS) and detective quantum efficiency (DQE) were measured for six mammography systems that utilized these different detectors. A new method to reconstruct anisotropic 2D presampling MTF matrices from 1D radial MTFs measured along different angular directions across the detector is described; an image of a sharp, circular disc was used for this purpose. The effective pixel fill factor for the FP systems was determined from the axial 1D presampling MTFs measured with a square sharp edge along the two orthogonal directions of the pixel lattice. Expectation MTFs were then calculated by averaging the radial MTFs over all possible phases and the 2D EMTF formed with the same reconstruction technique used for the 2D presampling MTF. The quantum NPS was then established by noise decomposition from homogenous images acquired as a function of detector air kerma. This was further decomposed into the correlated and uncorrelated quantum components by fitting the radially averaged quantum NPS with the radially averaged EMTF(2). This whole procedure allowed a detailed analysis of the influence of aliasing, signal and noise decorrelation, x-ray capture efficiency and global secondary gain on NPS and detector DQE. The influence of noise statistics, pixel fill factor and additional electronic and fixed pattern noises on the DQE was also studied. The 2D cascaded model and decompositions performed on the acquired images also enlightened the observed quantum NPS and DQE anisotropy.
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Scientific studies regarding specifically references do not seem to exist. However, the utilization of references is an important practice for many companies involved in industrial marketing. The purpose of the study is to increase the understanding about the utilization of references in international industrial marketing in order to contribute to the development of a theory of reference behavior. Specifically, the modes of reference usage in industry, the factors affecting a supplier's reference behavior, and the question how references are actually utilized, are explored in the study. Due to the explorative nature of the study, a research design was followed where theory and empirical studies alternated. An Exploratory Framework was developed to guide a pilot case study that resulted in Framework 1. Results of the pilot study guided an expanded literature review that was used to develop first a Structural Framework and a Process Framework which were combined in Framework 2. Then, the second empirical phase of the case study was conducted in the same (pilot) case company. In this phase, Decision Systems Analysis (DSA) was used as the analysis method. The DSA procedure consists of three interviewing waves: initial interviews, reinterviews, and validating interviews. Four reference decision processes were identified, described and analyzed in the form of flowchart descriptions. The flowchart descriptions were used to explore new constructs and to develop new propositions to develop Framework 2 further. The quality of the study was ascertained by many actions in both empirical parts of the study. The construct validity of the study was ascertained by using multiple sources of evidence and by asking the key informant to review the pilot case report. The DSA method itself includes procedures assuring validity. Because of the choice to conduct a single case study, external validity was not even pursued. High reliability was pursued through detailed documentation and thorough reporting of evidence. It was concluded that the core of the concept of reference is a customer relationship regardless of the concrete forms a reference might take in its utilization. Depending on various contingencies, references might have various tasks inside the four roles of increasing 1) efficiency of sales and sales management, 2) efficiency of the business, 3) effectiveness of marketing activities, and 4) effectiveness in establishing, maintaining and enhancing customer relationships. Thus, references have not only external but internal tasks as well. A supplier's reference behavior might be affected by many hierarchical conditions. Additionally, the empirical study showed that the supplier can utilize its references as a continuous, all pervasive decision making process through various practices. The process includes both individual and unstructured decision making subprocesses. The proposed concept of reference can be used to guide a reference policy recommendable for companies for which the utilization of references is important. The significance of the study is threefold: proposing the concept of reference, developing a framework of a supplier's reference behavior and its short term process of utilizing references, and conceptual structuring of an unstructured and in industrial marketing important phenomenon to four roles.
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Effects-Based Operations (EBO) sekä siitä kehittynyt Effects-Based Approach to Operations ovat nykyajan operatiivisen sekä strategisen tason suunnittelun avainkäsitteitä Natossa ja useissa sen kumppani valtioissa. Konsepti on levinnyt maailmalle alun perin Yhdysvaltojen asevoimista, mutta viimeaikaisten kokemusten perusteella Yhdysvallat on kuitenkin luopumassa konseptista. United States Joint Forces Command (USJFCOM) on antanut käskyn poistaa yhteisoperaatioiden suunnittelutason käytöstä sellaiset käsitteet, kuten EBO, System-of-Systems Analysis sekä Operational Net Assessment. Tutkimuksen tarkoituksena on selvittää julkisten yhdysvaltalaisten sotilaslähteiden sisältöanalyysin kautta, mitkä syyt ovat johtaneet EBO:sta luopumiseen sekä mitä sen tilalle ollaan kehittämässä. Tutkimuksen perusteella tultiin seuraaviin johtopäätöksiin: (1) Yhdysvaltojen asevoimat ovat luopumassa yhteisoperaatioiden tasolla EBO konseptista. (2) Vuodesta 2007 maavoimat eivät käytä EBO konseptia omassa suunnitteluprosessissaan. (3) EBO:sta luopumisen syyt ovat seuraavat: (a) EBO:sta on eri asiakirjoissa eri tulkintoja ja siitä käytetään eri käsitteitä, mikä aiheuttaa hämmennystä; (b) EBO:ssa käytettävä tehtävän määrittely on aiheuttanut sekaannusta; (c) EBO:n suunnitteluprosessi on liian tieteellinen ja monimutkainen. Ei ole mahdollista ennustaa tarkasti oman toiminnan mahdollisia vaikutuksia monimutkaisia avoinna olevia järjestelmiä vastaan. Tieteellisyys heikentää komentajien sotataidollista ajattelua ja ongelman määrittelyä; (d) Johtamistapa ei ole enää johtajakeskeistä, koska komentajat keskittyvät liikaa yksityiskohtiin ja oikean ongelmanratkaisuun keskittyminen häviää valtavaan informaatiovirtaan; (e) EBO pakottaa keskitettyyn johtamistapaan, mikä pienentää alaisten aloitekykyä eikä mahdollista nykyaikaisessa erittäin monimutkaisessa toimintaympäristössä nopeaa reagointia yllättäviin tilanteisiin. (4) Yhteisoperaatioiden tasolla tullaan EBO:n sijaan kehittämään Operational Design konseptia, jossa otetaan esimerkkiä maavoimilta sekä merijalkaväeltä. (5) Operational Design on filosofinen systemaattinen analyysimenetelmä, joka pyrkii koko operaation ajan tarkistamaan yhtymän keskittymistä oikeaan ongelmanratkaisuun. (6) Operational Design mahdollistaa komentajakeskeisen lähestymistavan ongelmiin ja sopii monimutkaisia avoimia järjestelmiä vastaan. Operational Design mahdollistaa sotataidollisen ajattelun ja sopii paremmin ennustamattomien ja yllättävien tilanteiden ratkaisemiseen.
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Kirjallisuusarvostelu
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Toisen jäte on toisen raaka-aine – Kierrätys ja uudelleenvalmistus taloudellisesti ja ekologisesti kestävänä liiketoimintamahdollisuutena Väitöskirjatutkimus tarkastelee kierrätystä ja uudelleenvalmistusta sekä siihen perustuvaa kierrätysliiketoimintaa taloudellisesti ja ekologisesti kestävänä liiketoimintamahdollisuutena. Tässä kestävyys tarkoittaa jätekysymysten ratkaisemista tavalla, joka mahdollistaa kestävän kehityksen periaatteiden mukaisen yhteiskunnan kehittymisen. Jätteisiin liittyvät taloudelliset ja ekolo- giset kysymykset ovat merkittävä yhteiskunnallinen haaste. Tämä luo tarpeen tutkimukselle, jonka lähtökohtana on jätekysymysten moniulotteinen tarkas- telu ja yksittäisen yrityksen toiminnan suhteuttaminen osaksi laajempaa kokonaisuutta. Tässä tutkimuksessa jätteen hyödyntämistä materiaalina lähestytään sekä empiirisesti yrityksen näkökulmasta että teoreettisesti systeemiajattelun tarjoamasta laajemmasta perspektiivistä. Tutkimuksen tavoitteena on ymmär- tää kierrätystä ja uudelleenvalmistusta liiketoimintamahdollisuutena, niiden merkitystä yrityksessä, alueella ja kierrätystaloudessa sekä näiden vuorovai- kutteista suhdetta taloudelliseen ja ekologiseen kestävyyteen nähden. Tutki- muskysymys on tärkeä, koska siihen vastaamalla syvennetään ymmärrystä yrityksissä tapahtuvan kierrätyksen ja uudelleenvalmistuksen merkityksestä kestävämmän yhteiskunnan rakentumisessa. Tutkimuksen teoriaperusta pohjautuu teollisen ekologian kirjallisuuteen ja ekoteollisen kehityksen tutkimukseen. Kierrätysliiketoiminnan kestävyyden tarkastelu rakentuu tutkimuksessa teollisen ekologian ja ekoteollisen kehityk- sen lähtökohtana olevaan win-win-ajatteluun, jonka mukaan hyvä ympäristö- suorituskyky ja hyvä taloudellinen suorituskyky voivat vahvistaa toisiaan. Kierrätysliiketoiminnan teoreettisessa tarkastelussa keskeisiä elementtejä ovat kierrätystalouden malli, teollisen ekologian alueelliset systeemit, ekoteolliset verkostot ja yrityksen rooli teollista ekologiaa soveltavana toimijana. Tutki- muksen keskeisenä kontribuutiona on yritysnäkökulman integroiminen aiem- paa vahvemmin osaksi teollisen ekologian diskursseja. Kierrätysliiketoiminnan taloudelliseen ja ekologiseen kannattavuuteen ja sen myötä kestävyyteen liittyviä kysymyksiä on lähestytty tekemällä yritys- haastatteluja ja hyödyntämällä valmista haastatteluaineistoa. Tutkimusta varten haastattelin 10 kierrätysliiketoimintaa harjoittavaa yritystä vuosina 2007 ja 2008. Tämän lisäksi tutkimuksessa on hyödynnetty Turun ammatti- korkeakoulun ja Turku Science Parkin toteuttamassa RESU-hankkeessa (Kierrätysliiketoiminta ja resurssitehokkuus Varsinais-Suomen vahvuudeksi – RESU) vuosina 2013 ja 2014 kerättyä aineistoa. Hankkeessa haastateltiin yhteensä 25 jätemateriaalia hyödyntävää ja/tai tuottavaa yritystä. Aineistojen analysointimenetelmänä on sisällönanalyysi. Analyysin tulok- sena muodostettiin yhteensä viisi pääteemaa ja 12 alateemaa. Teemat kuvaavat kierrätysliiketoimintaa aiempaa moniulotteisemmin ja näin syventävät ymmär- rystä ilmiön merkityksestä kestävämmän yhteiskunnan rakentumisessa. Teolli- sen ekologian alaan kuuluvat kvalitatiiviset tutkimukset ovat melko harvinai- sia, joten tämän väitöstutkimuksen ilmeisenä vahvuutena on laadullisen tutkimusmenetelmän hyödyntäminen. Tutkimuksen tuloksena voidaan todeta, että kierrätystalouden kehittymistä edistävä kierrätysliiketoiminta on monimuotoista ja sisältää erilaisia liiketoi- mintamahdollisuuksia sekä arvoketjuja. Paikallistuntemus ja keskeinen sijainti jätemateriaalien tuottajien suhteen on tärkeä kriteeri kierrätysliiketoiminnassa, mutta jätemateriaaleja myös kuljetetaan pitkiä matkoja. Paikallisia tai alueelli- sia jätevirtoja hyödyntävä kierrätysliiketoiminta voi tukea alueellista kestä- vyyttä, mutta toisinaan myös keskitetty hyödyntäminen voi olla kestävä vaih- toehto. Yhteistyöverkostot ovat tärkeitä jätemateriaalin laadun ja saatavuuden näkökulmasta. Tutkimus osoittaa, että kierrätysliiketoimintaa harjoittavat yritykset ovat samalla sekä kierrätystalouden käytännön toimeenpanijoita että uuden toimintakulttuurin luojia. Tutkimuksen tulosten perusteella voidaan esittää johtopäätös, että kierrä- tysliiketoiminta on taloudellisesti ja ekologisesti kannattava liiketoimintamah- dollisuus. Win-win-ratkaisut eivät kuitenkaan takaa kierrätysliiketoiminnan kestävyyttä. Kierrätysliiketoiminnan kestävyyden arvioiminen edellyttää laajaa perspektiiviä ja toiminnan vaikutusten suhteuttamista mittakaavaan, ajalliseen ulottuvuuteen, interventioon ja sosiaalisiin kysymyksiin. Teolliseen ekologiaan perustuva kierrätysliiketoiminta luo mahdollisuuksia edistää kestävyyttä, joten tällä perusteella kierrätystä ja uudelleenvalmistusta voidaan pitää kestävänä liiketoimintamahdollisuutena. Avainsanat: kierrätysliiketoiminta, kierrätys, uudelleenvalmistus, systeemiajattelu, teollinen ekologia, ekoteollinen kehitys, kierrätystalous, win-win-ajattelu, kestävyys One company's waste is another's raw material –Recycling and remanufacturing as an economically and environmentally sustainable business opportunity The thesis investigates whether product recycling and remanufacturing can serve as a business opportunity that is economically and ecologically sustaina- ble. In this effort, my idea is to contribute to solving the waste issue in a manner that makes it possible to strive toward sustainable societal develop- ment. The economic and ecological questions associated with waste flows are a significant challenge. The complexity of the issue requires a multidimen- sional approach in which the operation of an individual company is viewed in the context of the larger societal system. In this thesis waste utilization as a resource with value is considered both from an empirical perspective on the firm as well as from a more general viewpoint offered by systems analysis. The objective of the thesis is to under- stand recycling and remanufacturing as a business opportunity. The thesis considers the meaning of recycling and remanufacturing for a single company, for the region the company is located and for the recycling economy. The objective of this study is important for it enhances the understanding of the product recycling and remanufacturing processes that take place within busi- ness organizations and how these processes affect societal sustainable development. The theoretical basis arises from industrial ecology and from the literature on eco-industrial development. The business-economic win-win situation and this vision serve as the basic position from which recycling business is inves- tigated in the thesis. In the theoretical discussion, key elements are recycling economy model, regional and local industrial ecosystems, eco-industrial networks and the role of a company as an actor that applies industrial ecology in practice. The main contribution of this study lies in integrating the company perspective more strongly into the industrial ecology discourses. The recycling business has been studied by conducting interviews in companies and by secondary analysis of an existing interview material. During 2007 and 2008 I made 10 interviews in companies that are active in recycling business. In addition, I used interview material gathered for the project “Recycling business and resource efficiency as the strength of Southwest Finland” (RESU) by Turku University of Applied Sciences and Turku Science Park during the period 2013–2014. This data covers altogether 25 businesses that either utilize and/or produce waste materials. The data has been analyzed using the content analysis method. This process led to the development of 5 main themes and 12 sub-themes. These themes describe the recycling business multi-dimensionally and thus understanding of the phenomenon and its role in building a sustainable society are substantially deepened in this research. In the field of industrial ecology qualitative studies are relatively rare and therefore the qualitative research approach is an evident strength of the thesis. The results show that the recycling business activity supporting recycling economy has diverse dimensions including various business opportunities and diverse value chains. The results show that for waste producers it is important to know the local situational factors and to have a central geographical location. Waste materials are, however, transported over long distances as well. The study indicates that local waste flow utilization can support regional sustainability, while occasionally a more centralized utilization can be sustain- able. Collaboration networks are important to secure the quality and availabil- ity of utilizable waste materials. The thesis demonstrates that the companies practicing recycling business serve simultaneously as actors that implement recycling economy and enhance a new operation culture within the business community. The overall conclusion of the thesis argues that recycling business is a business opportunity that can support both an economically and environmen- tally viable business operation. However, win-win solutions do not secure the sustainability of recycling business. The sustainability evaluation of recycling business requires a holistic systems perspective. The actions undertaken need to be considered with changing spatial and temporal system boundaries, societal intervention and placed in the context of relevant societal issues. Industrial ecology -based recycling business creates opportunities for sustain- ability and thus recycling and remanufacturing present an opportunity for sustainable business. Keywords: Recycling business; Recycling; Remanufacturing, Systems thinking; Industrial ecology; Eco-industrial development; Recycling Economy; Win-Win thinking; Sustainability
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The present world energy production is heavily relying on the combustion of solid fuels like coals, peat, biomass, municipal solid waste, whereas the share of renewable fuels is anticipated to increase in the future to mitigate climate change. In Finland, peat and wood are widely used for energy production. In any case, the combustion of solid fuels results in generation of several types of thermal conversion residues, such as bottom ash, fly ash, and boiler slag. The predominant residue type is determined by the incineration technology applied, while its composition is primarily relevant to the composition of fuels combusted. An extensive research has been conducted on technical suitability of ash for multiple recycling methods. Most of attention was drawn to the recycling of the coal combustion residues, as coal is the primary solid fuel consumed globally. The recycling methods of coal residues include utilization in a cement industry, in concrete manufacturing, and mine backfilling, to name few. Biomass combustion residues were also studied to some extent with forest fertilization, road construction, and road stabilization being the predominant utilization options. Lastly, residues form municipal solid waste incineration attracted more attention recently following the growing number of waste incineration plants globally. The recycling methods of waste incineration residues are the most limited due to its hazardous nature and varying composition, and include, among others, landfill construction, road construction, mine backfilling. In the study, environmental and economic aspects of multiple recycling options of thermal conversion residues generated within a case-study area were studied. The case-study area was South-East Finland. The environmental analysis was performed using an internationally recognized methodology — life cycle assessment. Economic assessment was conducted applying a widely used methodology — cost-benefit analysis. Finally, the results of the analyses were combined to enable easier comparison of the recycling methods. The recycling methods included the use of ash in forest fertilization, road construction, road stabilization, and landfill construction. Ash landfilling was set as a baseline scenario. Quantitative data about the amounts of ash generated and its composition was obtained from companies, their environmental reports, technical reports and other previously published literature. Overall, the amount of ash in the case-study area was 101 700 t. However, the data about 58 400 t of fly ash and 35 100 t of bottom ash and boiler slag were included in the study due to lack of data about leaching of heavy metals in some cases. The recycling methods were modelled according to the scientific studies published previously. Overall, the results of the study indicated that ash utilization for fertilization and neutralization of 17 600 ha of forest was the most economically beneficial method, which resulted in the net present value increase by 58% compared to ash landfilling. Regarding the environmental impact, the use of ash in the construction of 11 km of roads was the most attractive method with decreased environmental impact of 13% compared to ash landfilling. The least preferred method was the use of ash for landfill construction since it only enabled 11% increase of net present value, while inducing additional 1% of negative impact on the environment. Therefore, a following recycling route was proposed in the study. Where possible and legally acceptable, recycle fly and bottom ash for forest fertilization, which has strictest requirements out of all studied methods. If the quality of fly ash is not suitable for forest fertilization, then it should be utilized, first, in paved road construction, second, in road stabilization. Bottom ash not suitable for forest fertilization, as well as boiler slag, should be used in landfill construction. Landfilling should only be practiced when recycling by either of the methods is not possible due to legal requirements or there is not enough demand on the market. Current demand on ash and possible changes in the future were assessed in the study. Currently, the area of forest fertilized in the case-study are is only 451 ha, whereas about 17 600 ha of forest could be fertilized with ash generated in the region. Provided that the average forest fertilizing values in Finland are higher and the area treated with fellings is about 40 000 ha, the amount of ash utilized in forest fertilization could be increased. Regarding road construction, no new projects launched by the Center of Economic Development, Transport and the Environment in the case-study area were identified. A potential application can be found in the construction of private roads. However, no centralized data about such projects is available. The use of ash in stabilization of forest roads is not expected to increased in the future with a current downwards trend in the length of forest roads built. Finally, the use of ash in landfill construction is not a promising option due to the reducing number of landfills in operation in Finland.
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Les objets d’étude de cette thèse sont les systèmes d’équations quasilinéaires du premier ordre. Dans une première partie, on fait une analyse du point de vue du groupe de Lie classique des symétries ponctuelles d’un modèle de la plasticité idéale. Les écoulements planaires dans les cas stationnaire et non-stationnaire sont étudiés. Deux nouveaux champs de vecteurs ont été obtenus, complétant ainsi l’algèbre de Lie du cas stationnaire dont les sous-algèbres sont classifiées en classes de conjugaison sous l’action du groupe. Dans le cas non-stationnaire, une classification des algèbres de Lie admissibles selon la force choisie est effectuée. Pour chaque type de force, les champs de vecteurs sont présentés. L’algèbre ayant la dimension la plus élevée possible a été obtenues en considérant les forces monogéniques et elle a été classifiée en classes de conjugaison. La méthode de réduction par symétrie est appliquée pour obtenir des solutions explicites et implicites de plusieurs types parmi lesquelles certaines s’expriment en termes d’une ou deux fonctions arbitraires d’une variable et d’autres en termes de fonctions elliptiques de Jacobi. Plusieurs solutions sont interprétées physiquement pour en déduire la forme de filières d’extrusion réalisables. Dans la seconde partie, on s’intéresse aux solutions s’exprimant en fonction d’invariants de Riemann pour les systèmes quasilinéaires du premier ordre. La méthode des caractéristiques généralisées ainsi qu’une méthode basée sur les symétries conditionnelles pour les invariants de Riemann sont étendues pour être applicables à des systèmes dans leurs régions elliptiques. Leur applicabilité est démontrée par des exemples de la plasticité idéale non-stationnaire pour un flot irrotationnel ainsi que les équations de la mécanique des fluides. Une nouvelle approche basée sur l’introduction de matrices de rotation satisfaisant certaines conditions algébriques est développée. Elle est applicable directement à des systèmes non-homogènes et non-autonomes sans avoir besoin de transformations préalables. Son efficacité est illustrée par des exemples comprenant un système qui régit l’interaction non-linéaire d’ondes et de particules. La solution générale est construite de façon explicite.
Resumo:
This paper introduces how artificial intelligence technologies can be integrated into a known computer aided control system design (CACSD) framework, Matlab/Simulink, using an object oriented approach. The aim is to build a framework to aid supervisory systems analysis, design and implementation. The idea is to take advantage of an existing CACSD framework, Matlab/Simulink, so that engineers can proceed: first to design a control system, and then to design a straightforward supervisory system of the control system in the same framework. Thus, expert systems and qualitative reasoning tools are incorporated into this popular CACSD framework to develop a computer aided supervisory system design (CASSD) framework. Object-variables an introduced into Matlab/Simulink for sharing information between tools