960 resultados para Homogenization Schemes
Resumo:
Two simple sensitive and cost-effective spectrophotometric methods are described for the determination of lansoprazole (LPZ) in bulk drug and in capsules using ceric ammonium sulphate (CAS), iron (II), orthophenanthroline and thiocyanate as reagents. In both methods, an acidic solution of lansoprazole is treated with a measured excess of CAS followed by the determination of unreacted oxidant by two procedures involving different reaction schemes. The first method involves the reduction of residual oxidant by a known amount of iron(II), and the unreacted iron(II) is complexed with orthophenanthroline at a raised pH, and the absorbance of the resulting complex measured at 510 nm (method A). In the second method, the unreacted CAS is reduced by excess of iron (II), and the resulting iron (III) is complexed with thiocyanate in the acid medium and the absorbance of the complex measured at 470 nm (method B). In both methods, the amount CAS reacted corresponds to the amount of LPZ. In method A, the absorbance is found to increase linearly with the concentration of LPZ where as in method B a linear decrease in absorbance occurs. The systems obey Beer's law for 2.5-30 and 2.5-25 µg mL-1 for method A and method B, respectively, and the corresponding molar absorptivity values are 8.1×10³ and 1.5×10(4) L mol-1cm-1 . The methods were successfully applied to the determination of LPZ in capsules and the results tallied well with the label claim. No interference was observed from the concomitant substances normally added to capsules.
Resumo:
Two sensitive spectrophotometric methods are described for the determination of lansoprazole (LPZ) in bulk drug and in capsule formulation. The methods are based on the oxidation of lansoprazole by insitu generated bromine followed by determination of unreacted bromine by two different reaction schemes. In one procedure (method A), the residual bromine is treated with excess of iron (II), and the resulting iron (III) is complexed with thiocyanate and measured at 470 nm. The second approach (method B) involves treating the unreacted bromine with a measured excess of iron (II) and remaining iron (II) is complexed with orthophenanthroline at a raised pH, and measured at 510 nm. In both methods, the amount of bromine reacted corresponds to the amount of LPZ. The experimental conditions were optimized. In method A, the absorbance is found to decrease linearly with the concentration of LPZ (r = -0.9986) where as in the method B a linear increase in absorbance occurs (r = 0.9986) The systems obey Beer's law for 0.5-4.0 and 0.5-6.0 µg mL-1 for method A and method B, respectively. The calculated molar absorptivity values are 3.97µ10(4) and 3.07µ10(4) L mol-1cm-1 for method A and method B, respectively, and the corresponding Sandell sensitivity values are 0.0039 and 0.0013 µg cm-2. The limit of detection (LOD) and quantification (LOQ) are also reported for both methods. Intra-day and inter-day precision, and accuracy of the methods were established as per the current ICH guidelines. The methods were successfully applied to the determination of LPZ in capsules and the results tallied well with the label claim and the results were statistically compared with those of a reference method by applying the Student's t-test and F-test. No interference was observed from the concomitant substances normally added to capsules. The accuracy and validity of the methods were further ascertained by performing recovery experiments via standard-addition method.
Resumo:
Two sensitive spectrophotometric methods are described for the determination of simvastatin (SMT) in bulk drug and in tablets. The methods are based on the oxidation of SMT by a measured excess of cerium (IV) in acid medium followed by determination of unreacted oxidant by two different reaction schemes. In one procedure (method A), the residual cerium (IV) is reacted with a fixed concentration of ferroin and the increase in absorbance is measured at 510 nm. The second approach (method B) involves the reduction of the unreacted cerium (IV) with a fixed quantity of iron (II), and the resulting iron (III) is complexed with thiocyanate and the absorbance measured at 470 nm. In both methods, the amount of cerium (IV) reacted corresponds to SMT concentration. The experimental conditions for both methods were optimized. In method A, the absorbance is found to increase linearly with SMT concentration (r = 0.9995) whereas in method B, the same decreased (r = -0.9943). The systems obey Beer's law for 0.6-7.5 and 0.5-5.0 µg mL-1 for method A and method B, respectively. The calculated molar absorptivity values are 2.7 X 10(4) and 1.06 X 10(5) Lmol-1 cm-1, respectively; and the corresponding sandel sensitivity values are 0.0153 and 0.0039µg cm-2, respectively. The limit of detection (LOD) and quantification (LOQ) are reported for both methods. Intra-day and inter-day precision, and accuracy of the methods were established as per the current ICH guidelines. The methods were successfully applied to the determination of SMT in tablets and the results were statistically compared with those of the reference method by applying the Student's t-test and F-test. No interference was observed from the common excipients added to tablets. The accuracy and validity of the methods were further ascertained by performing recovery experiments via standard addition procedure.
Resumo:
The increasing power demand and emerging applications drive the design of electrical power converters into modularization. Despite the wide use of modularized power stage structures, the control schemes that are used are often traditional, in other words, centralized. The flexibility and re-usability of these controllers are typically poor. With a dedicated distributed control scheme, the flexibility and re-usability of the system parts, building blocks, can be increased. Only a few distributed control schemes have been introduced for this purpose, but their breakthrough has not yet taken place. A demand for the further development offlexible control schemes for building-block-based applications clearly exists. The control topology, communication, synchronization, and functionality allocationaspects of building-block-based converters are studied in this doctoral thesis. A distributed control scheme that can be easily adapted to building-block-based power converter designs is developed. The example applications are a parallel and series connection of building blocks. The building block that is used in the implementations of both the applications is a commercial off-the-shelf two-level three-phase frequency converter with a custom-designed controller card. The major challenge with the parallel connection of power stages is the synchronization of the building blocks. The effect of synchronization accuracy on the system performance is studied. The functionality allocation and control scheme design are challenging in the seriesconnected multilevel converters, mainly because of the large number of modules. Various multilevel modulation schemes are analyzed with respect to the implementation, and this information is used to develop a flexible control scheme for modular multilevel inverters.
Resumo:
Tämä opinnäytetyö on tehty yhteistyössä Lappeenrannan teknillisen yliopiston ja Enviroc Oy:n kanssa. Työn tarkoituksena on ollut kehittää suomalaisiin olosuhteisiin soveltuva laskentamalli purku- ja korjausrakentamiskohteiden hiilijalanjäljelle. Kehitettyä mallia voi käyttää yrityksessä lainsäädännön vaatimusten noudattamisen todentamiseen sekä purku- ja korjausrakentamiskohteiden toimintatapojen vertailuun. Työssä käsitellään purku- ja korjausrakentamiskohteiden hiilijalanjälkeen vaikuttavia asioita, joita ovat työmaan energiankulutus sekä syntyvien jätteiden lajittelu, kuljetukset, käsittely ja hyödyntäminen tai loppusijoitus. Laskentamalli on kehitetty laskemalla esimerkkikohteille hiilijalanjäljet elinkaarimallintamisen avulla. Työssä on tarkasteltu myös vaihtoehtoisia jäteskenaarioita sekä laskentamallin luotettavuutta. Työn lopputuloksena on saatu kolmen eri kokoluokan esimerkkikohteen hiilijalanjäljet ja laskentamallin periaatekaaviot. Jätteiden toimituspisteiden ja jätejakeiden kulkureittien vaihtelevuuden sekä eri kohteista muodostuvien erityyppisten jätejakeiden johdosta yhden kokonaisvaltaisen laskentamallin kehittäminen on haasteellista. Myös tietojen hankinta kohteista ja jatkokäsittelyistä ja etenkin primääritietojen saaminen on ongelmallista. Tämänhetkinen laskentamalli perustuu enimmäkseen sekundääritietoihin ja arvioihin, joten mallin luotettavuuden lisäämiseksi olisi panostettava primääritiedon määrän lisäämiseen. Laskennan perusteella jäteskenaariovaihtoehdoista lajitteleva toimintamalli osoittautui hiilijalanjäljen kannalta suotuisimmaksi pienemmissä kohteissa ja käsittelylaitospainotteinen malli suuressa kohteessa. Merkittäviä tekijöitä kohteiden hiilijalanjälkien muodostumiselle olivat metallien käsittely, jätteiden poltto sekä neitsytraaka-aineista valmistetun teräksen ja fossiilisten polttoaineiden vältetyt päästöt. Merkittävimmiksi kasvihuonekaasuiksi purku- ja korjausrakentamiskohteiden laskennassa osoittautuivat hiilidioksidin lisäksi halogenoidut hiilivedyt ja metaani.
Resumo:
Tutkimuksessa luodaan Tuko Logistics Oy:n työntömastotrukkien toimintaa opti-moivia toimintaehdotuksia varastonohjausjärjestelmästä saatavan työntömastotruk-kidatan pohjalta. Tutkimus on toteutettu haastattelututkimuksena ja käyttäen apuna tieteellisiä julkaisuja. Tehtävien lomittamistutkimuksen ja loogiseen päättelyn tulok-sena on luotu kaksi toimintaehdotusta: A ja B. Toimintaehdotusten vaikutuksia van-haan järjestelmään verrataan mittareilla, joista osa on tehty jonoteorian jonomallien laskukaavojen pohjalta. Mittareita ovat: tehdyt tehtävät tunnissa, tuottamattoman ajon suhde tuottavaan, normaalitehtäväjonon pituus ja normaalitehtäväjonon koko-naisodotusaika. Toimintaehdotus B osoittautuu tehokkaammaksi ehdotukseksi, mutta Toimintaehdotus A:lla voi varmistaa tehtävien riittämisen työntömastotrukeille. Tut-kimuksessa ehdotetaan myös muita työntömastotrukkien toimintaa optimoivia muu-toksia, jotka voidaan ottaa käyttöön jokaisessa toimintamallissa.
Resumo:
Organising the PT- programme for full-time working adult students is a challenging task as it is an international programme with both domestic and foreign students with different educational background. The purpose of this project work is to provide both student and lecturer feedback for improving Master Of Science Degree Programme in Packaging Technology to meet better the requirements of part-time studying. The objective of this work is in accordance with the Lappeenranta University of Technology’s strategy to improve continuously degree programmes and courses and to use student feedback in this development work of education. Matters, such as lecture schemes, distance material distribution, distance assignment handling, course assessments, and guidance of thesis work will be under scrutiny.
Resumo:
Lean –filosofia on ollut 1990 lähtien esillä yritysten toiminnan kehittämisessä niin laadun kuin tuottavuuden kehittämisen osalla. Filosofia on rakennettu Toyotan kehittämän Toyota Production Systemin (TPS) pohjalta ja sisältää useita eri menetelmiä yrityksen toimintojen jatkuvaan kehittämiseen yrityksen eri vaiheissa. Lean –filosofiassa yritystä kehitetään koko yrityksen olemassa olon ajan, voidaankin sanoa kyseessä olevan yrityksen elämäntapa. VR Group:n kunnossapitopalveluissa kehitetään parhaillaan VR Groupin laitteiden kunnossapitoa vastaamaan tulevaisuudessa avautuvaan kilpailuun. Kehittämishankkeen yhtenä kohteena on lean –ajattelun käyttöönottaminen kunnossapitopalvelun toiminnassa. Työssä selvitettiin leanin sisältämien menetelmien käyttöönottoa yhdelle VR Groupin kunnossapitoyksikölle, pääpainona virtauttaminen sekä jatkuva parantaminen. Työssä laadittiin kaksi virtauttamissuunnitelmaa VR Groupin kunnossapitoyksikölle, sekä esitellään vaihtoehtoja lean -työkaluista, joita kohdeyksikön kehittämisohjelmassa voitaisiin käyttää.
Resumo:
Comprehensive understanding of the heat transfer processes that take place during circulating fluidized bed (CFB) combustion is one of the most important issues in CFB technology development. This leads to possibility of predicting, evaluation and proper design of combustion and heat transfer mechanisms. The aim of this thesis is to develop a model for circulating fluidized bed boiler operation. Empirical correlations are used for determining heat transfer coefficients in each part of the furnace. The proposed model is used both in design and offdesign conditions. During off-design simulations fuel moisture content and boiler load effects on boiler operation have been investigated. In theoretical part of the thesis, fuel properties of most typical classes of biomass are widely reviewed. Various schemes of biomass utilization are presented and, especially, concerning circulating fluidized bed boilers. In addition, possible negative effects of biomass usage in boilers are briefly discussed.
Resumo:
Tausta Kansainvälinen kauppa on globaalia toimintaa, jossa tavaroiden ja palveluiden tuottaminen ja kuluttaminen on jakautunut maapallon eri osiin. Arvoketjukäsitteellä korostetaan eri toimijoiden panosta lopputuotteen valmistamiseksi, sekä yhteisten tavoitteiden merkitystä. Toimijaverkostot ovat moni-ilmeisiä ja monimutkaisia. Globaalin kaupan toinen tärkeä piirre on yhteiskuntavastuu, joka tulee esiin niin yksityisen kuin julkisen sektorin toiminnassa. Sen toteuttaminen asettaa suuria haasteita sekä yksityisen että julkisen sektorin toimijoille. Kansallisvaltion mahdollisuudet hallita globaaleja kaupan arvoketjuja julkisella sääntelyllä on osoittautunut ongelmalliseksi. Tutkimuskysymykset Tämä tutkimus on oikeustieteen alaan kuuluva sääntelytutkimuksen artikkeliväitöskirja, joka on tutkimusotteeltaan poikkitieteellinen. Tutkimus pyrkii kaikkiaan valaisemaan yksityisen sääntelyn käyttömahdollisuuksia ja rajoituksia elinkeinotoiminnassa. Keskeisessä roolissa oikeustieteen rinnalla on liiketaloustieteen tutkimus. Tutkimuskysymykset ovat ensinnäkin, mistä nousee kansainvälistä kauppaa koskeva yksityisen sääntelyn tarve ja toiseksi, mikä motivoi yrityksiä yksityiseen sääntelyyn tai itsesääntelyyn. Lopuksi pohditaan, miten lainsäätäjän tulisi suhtautua yksityiseen sääntelyyn. Tutkimuskysymyksiin vastaamalla syvennetään ja täsmennetään oikeustieteen piirissä tehtävää tutkimusta ennakoivasta oikeudesta. Menetelmät ja aineistot Tutkimus on oikeusvertaileva tutkimus, jossa pääpaino on yksityisessä sääntelyssä. Tutkimusaineisto nojautuu eri tieteenaloilla tehtyihin sekä kvalitatiivisiin että kvantitatiivisiin empiirisiin sääntelyjärjestelmien käyttöä ja toimivuutta koskeviin tutkimuksiin sekä tutkijan tekemään 42:en, metsäsektorin, elintarvikealan, vaatetusalan sekä vähittäiskaupan piirissä käytössä olevan sääntelyjärjestelmän analyysiin. Johtopäätökset Yksityisen sääntelyn tarve nousee tarpeesta hallita globaaleja arvoketjuja kohti yhteisiä tavoitteita. Tulevan lainsäädännön uhan sijasta yrityksiä motivoi yksityiseen sääntelyyn kilpailuedun tavoitteluun liittyvät tekijät. Koska kilpailuetuun yhä yleisemmin sisältyy yhteiskuntavastuullisuus, ovat yritysten tavoitteet ja julkisen sektorin tavoitteet lähentyneet. Erilaisten kansalaisjärjestöjen rooli kasvaa koko ajan. Ne osallistuvat vahvasti niin yksityisen sääntelyn laadintaan kuin myös sääntöjen valvontaan. Yksityisen sääntelyn tavoitteet ovat aiemmin liittyneet ympäristönsuojelun painottamiseen ja elintarviketurvallisuuteen erityisesti metsäsektorilla ja elintarvikealalla, myöhemmin sosiaalisen vastuullisuuden parantaminen on myös tullut painokkaammin esiin. Kansainvälisen kaupan piirissä syntynyttä yksityisen sääntelyn ilmiötä kuvataan tässä ennakoiva oikeus –käsitteellä. Aiempi tutkimus rajoittui tarkastelemaan ilmiötä vain ennakoivana lähestymistapana oikeuteen. Tässä painopiste on sen sijaan ennakoivan lähestymistavan avulla aikaansaaduissa sääntelyn välineissä ja lopputuloksissa: mahdollistavassa, valtaistavassa, dynaamisessa ja käyttäjäystävällisessä oikeudessa, jonka avulla luodaan mahdollisuuksia, ennalta ehkäistään ja hallitaan riskejä eikä pelkästään ratkaista jo syntyneitä ongelmia. Käsitteen sisältöä avataan tutkimuksessa sekä sääntelyjärjestelmien sisällöllisen tarkastelun että prosessiin liittyvän tarkastelun avulla.
Resumo:
As technology geometries have shrunk to the deep submicron regime, the communication delay and power consumption of global interconnections in high performance Multi- Processor Systems-on-Chip (MPSoCs) are becoming a major bottleneck. The Network-on- Chip (NoC) architecture paradigm, based on a modular packet-switched mechanism, can address many of the on-chip communication issues such as performance limitations of long interconnects and integration of large number of Processing Elements (PEs) on a chip. The choice of routing protocol and NoC structure can have a significant impact on performance and power consumption in on-chip networks. In addition, building a high performance, area and energy efficient on-chip network for multicore architectures requires a novel on-chip router allowing a larger network to be integrated on a single die with reduced power consumption. On top of that, network interfaces are employed to decouple computation resources from communication resources, to provide the synchronization between them, and to achieve backward compatibility with existing IP cores. Three adaptive routing algorithms are presented as a part of this thesis. The first presented routing protocol is a congestion-aware adaptive routing algorithm for 2D mesh NoCs which does not support multicast (one-to-many) traffic while the other two protocols are adaptive routing models supporting both unicast (one-to-one) and multicast traffic. A streamlined on-chip router architecture is also presented for avoiding congested areas in 2D mesh NoCs via employing efficient input and output selection. The output selection utilizes an adaptive routing algorithm based on the congestion condition of neighboring routers while the input selection allows packets to be serviced from each input port according to its congestion level. Moreover, in order to increase memory parallelism and bring compatibility with existing IP cores in network-based multiprocessor architectures, adaptive network interface architectures are presented to use multiple SDRAMs which can be accessed simultaneously. In addition, a smart memory controller is integrated in the adaptive network interface to improve the memory utilization and reduce both memory and network latencies. Three Dimensional Integrated Circuits (3D ICs) have been emerging as a viable candidate to achieve better performance and package density as compared to traditional 2D ICs. In addition, combining the benefits of 3D IC and NoC schemes provides a significant performance gain for 3D architectures. In recent years, inter-layer communication across multiple stacked layers (vertical channel) has attracted a lot of interest. In this thesis, a novel adaptive pipeline bus structure is proposed for inter-layer communication to improve the performance by reducing the delay and complexity of traditional bus arbitration. In addition, two mesh-based topologies for 3D architectures are also introduced to mitigate the inter-layer footprint and power dissipation on each layer with a small performance penalty.
Resumo:
Sustainability is the aim of forest management and forest regulation in many countries. Accordingly, forest management has been steered towards more environmentally friendly methods and new regulatory instruments have been introduced. At the same time, wood trade and forest industry have become a global business. Even if the importance of national forest legislation has not decreased, it has been widely acknowledged that national regulation of forest management is no longer sufficient. The movement of goods does not acknowledge boundaries, even though most negative environmental and social consequences stay in the country of origin of wood and other raw materials. As a partial solution to this dilemma, different kinds of regulations have been developed. Various forest certification schemes and wood trade regulation in the EU (995/2010) are examples of efforts to prevent illegal logging and unsustainable forestry. The Finland-based forest industry is to a varying extent dependent on wood trade from Russia. Especially in the 1990‟s, ethical questions concerning import of wood from Russian old growth forests near the Finnish border were widely discussed. Consequently, forest industry enterprises have developed systems to trace the origin of wood and to buy certified wood from Russia. The aim of the research has been to evaluate Finnish and Russian forest regulations in order to investigate what kind of forest management these regulations enhance, and to what extent ecologically sustainable forest management has been integrated into different forms of regulation. I have examined Finnish and Russian forest regulation in four separate articles based on the topics of the Russian Forest Code, forest certification and other voluntary forest protection measures in Russia, Finnish forest certification and Finnish forest legislation. One objective has been to analyse the roles voluntary forest certification plays in promoting sustainable forest management in different countries. In my research, I have mainly concentrated on ecological sustainability and protection of biodiversity, although other aspects of sustainable forest management have been touched upon in different articles. In the following I shall conclude the findings of my research. When the current Russian Forest Code (2006) was being adopted, the main emphasis was not on ecological issues, but on reorganizing forest governance. The role of ecological requirements was even slightly diminished during the legislative reform. There are, nevertheless, still stipulations aiming at ecological sustainability, such as the division of forests into different forest management categories and various protection zones. In 2000, FSC forest certification arrived in Russia, at present covering already 28 million hectares of forests. The PEFC scheme is now in use as well, but to a much lesser extent. If properly implemented, Russian forest certification schemes clearly improve the level of ecological and social sustainability of forestry in Russia. Certification criteria, however, are partly in conflict with the Russian forest legislation and certified enterprises have been forced to pay fines or to negotiate with forest authorities. This clearly indicates that even if Russian forest legislation has otherwise been liberalized to a certain extent, some significant paternalism still exists. Voluntary, hands-on biodiversity protection measures are not valued, and they are not part of the official protection policies as in many other countries. However, there have been some regional solutions to this dilemma. In the Republic of Karelia forest authorities have approved a set of forest biodiversity protection rules created by a local NGO and a forest industry enterprise. By following these local rules, an enterprise can avoid fines for protection measures. The current Finnish Forest Act was adopted in 1996. It brought forest legislation into a new era as some ecological aspects were integrated into forest legislation. The various soft-law forest management recommendations further increased the level of biodiversity protection. My evaluation of the overall legitimacy of the Finnish forest legislation and forest management paradigm revealed, however, several problematic issues. As part of this study I analysed the history of the current forest management paradigm. This analysis revealed the path dependency which still hinders the protection of biodiversity and clearly decreases the general legitimacy of forest management. Due to several historical reasons only even-structured forest management based on clear cuts has for decades been officially approved in Finland. Due to increasing demands of forest owners the legislation is finally being revised. Yet, the official approval of uneven-structured forest management would not be enough to fully improve ecological, social and cultural legitimacy. The latest ecological theories and knowledge of endangered species should be taken into account in the on-going reform of forest legislation as well as the modernisation. Forest legislation is one of the very few spheres of Finnish environmental legislation where openness and participation are still considered a threat. The first Finnish forest certification scheme, PEFC, was established in 2000. It now covers more than 20 million hectares, about 95% of the forests in Finland. PEFC Finland does not require a higher level of biodiversity protection than the recommendations by Tapio (the Development Centre for Forestry), but certification has unified forest management practices and requires more protection measures than mere forest legislation. The study suggests that in Finland PEFC has not functioned as an instrument which would substantially improve the level of forest management. Rather it has supported the status quo of the forest sector. While the ecological and social responsibility of Finland-based forest corporations was one impetus for this research, I want to conclude that there are problems related to forest legislation and non-state regulation in both Finland and Russia. If an enterprise buying wood from Russia buys only certified wood, and carefully avoids wood coming from high conservation value forests that are either ecologically or socially valuable, it can be claimed to be as sustainably produced as in Finland. However, there must be continuous scrutiny of the circumstances. In Russia, the level of the compliance of certification criteria varies considerably, and there are vast unprotected invaluable forest areas. The utilisation of these areas should not be based on short-sighted decisions or lack of consensus among stakeholders.
Resumo:
The thesis explores global and national-level issues related to the development of markets for biomass for energy. The thesis consists of five separate papers and provides insights on selected issues. The aim of Paper I was to identify methodological and statistical challenges in assessing international solid and liquid biofuels trade and provide an overview of the Finnish situation with respect to the status of international solid and liquid biofuels trade. We found that, for the Finnish case, it is possible to qualify direct and indirect trade volumes of biofuels. The study showed that indirect trade of biofuels has a highly significant role in Finland and may be a significant sector also in global biofuels trade. The purpose of Paper II was to provide a quantified insight into Finnish prospects for meeting the national 2020 renewable energy targets and concurrently becoming a largescale producer of forest-biomass-based second-generation biofuels for feeding increasing demand in European markets. We found that Finland has good opportunities to realise a scenario to meet 2020 renewable energy targets and for large-scale production of wood-based biofuels. The potential net export of transport biofuels from Finland in 2020 would correspond to 2–3% of European demand. Paper III summarises the global status of international solid and liquid biofuels trade as illuminated by several separate sources. International trade of biofuels was estimated at nearly 1 EJ for 2006. Indirect trade of biofuels through trading of industrial roundwood and material by-products comprises the largest proportion of the trading, with a share of about two thirds. The purpose of Paper IV was to outline a comprehensive picture of the coverage of various certification schemes and sustainability principles relating to the entire value-added chain of biomass and bioenergy. Regardless of the intensive work that has been done in the field of sustainability schemes and principles concerning use of biomass for energy, weaknesses still exist. The objective of Paper V was to clarify the alternative scenarios for the international biomass market until 2020 and identify the underlying steps needed toward a wellfunctioning and sustainable market for biomass for energy purposes. An overall conclusion drawn from this analysis concerns the enormous opportunities related to the utilisation of biomass for energy in the coming decades.
Resumo:
ABSTRACT This study aimed to compare thematic maps of soybean yield for different sampling grids, using geostatistical methods (semivariance function and kriging). The analysis was performed with soybean yield data in t ha-1 in a commercial area with regular grids with distances between points of 25x25 m, 50x50 m, 75x75 m, 100x100 m, with 549, 188, 66 and 44 sampling points respectively; and data obtained by yield monitors. Optimized sampling schemes were also generated with the algorithm called Simulated Annealing, using maximization of the overall accuracy measure as a criterion for optimization. The results showed that sample size and sample density influenced the description of the spatial distribution of soybean yield. When the sample size was increased, there was an increased efficiency of thematic maps used to describe the spatial variability of soybean yield (higher values of accuracy indices and lower values for the sum of squared estimation error). In addition, more accurate maps were obtained, especially considering the optimized sample configurations with 188 and 549 sample points.
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In this Thesis I discuss the dynamics of the quantum Brownian motion model in harmonic potential. This paradigmatic model has an exact solution, making it possible to consider also analytically the non-Markovian dynamics. The issues covered in this Thesis are themed around decoherence. First, I consider decoherence as the mediator of quantum-to-classical transition. I examine five different definitions for nonclassicality of quantum states, and show how each definition gives qualitatively different times for the onset of classicality. In particular I have found that all characterizations of nonclassicality, apart from one based on the interference term in the Wigner function, result in a finite, rather than asymptotic, time for the emergence of classicality. Second, I examine the diverse effects which coupling to a non-Markovian, structured reservoir, has on our system. By comparing different types of Ohmic reservoirs, I derive some general conclusions on the role of the reservoir spectrum in both the short-time and the thermalization dynamics. Finally, I apply these results to two schemes for decoherence control. Both of the methods are based on the non-Markovian properties of the dynamics.