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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

Sistema Inteligente Ágil de Processo Evolutivo - SIAPE: um protótipo brasileiro de sistemas EPS

Amaral, Hiram Carlos Costa 28 March 2016 (has links)
Submitted by Napoleana Barros Martins (napoleana_martins@hotmail.com) on 2016-08-01T15:38:31Z No. of bitstreams: 1 Dissertação Hiram Carlos Costa Amaral.pdf: 24315368 bytes, checksum: 3708b71cd79a7cfa94b2c34c95182cc2 (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2016-08-24T19:39:54Z (GMT) No. of bitstreams: 1 Dissertação Hiram Carlos Costa Amaral.pdf: 24315368 bytes, checksum: 3708b71cd79a7cfa94b2c34c95182cc2 (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2016-08-24T19:44:53Z (GMT) No. of bitstreams: 1 Dissertação Hiram Carlos Costa Amaral.pdf: 24315368 bytes, checksum: 3708b71cd79a7cfa94b2c34c95182cc2 (MD5) / Made available in DSpace on 2016-08-24T19:44:53Z (GMT). No. of bitstreams: 1 Dissertação Hiram Carlos Costa Amaral.pdf: 24315368 bytes, checksum: 3708b71cd79a7cfa94b2c34c95182cc2 (MD5) Previous issue date: 2016-03-28 / FAPEAM - Fundação de Amparo à Pesquisa do Estado do Amazonas / Manufacturing emerging paradigms have been used in an attempt to solve the problem of customization, i.e. the manufacture of products with mid and low batches and high variability. Namely Evolvable Production Systems (EPS) has been able to address the problem through the concept of mechatronics agents and a reversal of the local where intelligence (the production process) is in th the manufacturing system. However, there are still many gaps and barriers for the widespread use of EPS, namely the real prototypes that address the concepts of evolvable systems. This work presents the development of an evolvable system called Agile Intelligent System for Evolvable Process (SIAPE), which aimed adpats to demand variations and the evolution of the production system according to the changing of the product. To test the viability of SIAPE was first created a simplified automation prototype called Product UFAM which is compared with the SIAPE prototype itself among their compliance with the requirements of Industry Platform 4.0 (i4.0). / Paradigmas emergentes de fabricação têm sido usados na tentativa de solucionar o problema da customização, isto é, a manufatura de produtos em lotes baixos e com elevados níveis de variedades de produtos. Notadamente os Evolvable Production Systems (EPS) tem conseguido tratar o problema através do conceito de agentes mecatrônicos e de uma inversão do local de onde a inteligência do processo produtivo está dentro do sistema de manufatura. Entretanto, ainda há várias lacunas e barreiras ao amplo uso de EPS, dentre elas a necessidade de protótipos de sistemas que contemplem os conceitos de sistemas evolutivos. Este trabalho apresenta o desenvolvimento de um sistema evolutivo denominado de Sistema Inteligente Ágil de Processo Evolutivo - SIAPE que visa adaptação à demanda e a evolução do sistema produtivo de acordo com a evolução do produto. Para testar a viabilidade do SIAPE foi criado primeiramente um protótipo de automação simplificado chamado de Produto UFAM que é comparado com o protótipo SIAPE propriamente dito em torno de suas aderências às exigências da Plataforma da Indústria 4.0 (i4.0).
62

Concreto leve com pérolas de EPS: estudo de dosagens e de características mecânicas / Lightweight concrete with EPS beads: mix design and mechanical characteristics study

Bianca Pereira Moreira Ozório 12 December 2016 (has links)
Este trabalho teve como objetivo analisar o comportamento do concreto leve com pérolas de poliestireno expandido (expanded polystyrene – EPS), para posterior utilização em estruturas pré-moldadas constituídas, por exemplo, por painéis de paredes e lajes sujeitas a ações mecânicas. Também foram considerados parâmetros de durabilidade e mecanismos de redução da porosidade. Dentre um universo de solicitações a que as estruturas de concreto leve podem estar submetidas, analisaram-se, para diferentes dosagens: resistência à compressão axial, módulo de elasticidade, absorção de água, resistência à tração na compressão diametral e na flexão. Foram incorporadas pérolas de EPS como componente para proporcionar redução do peso do concreto. Esse concreto leve pode, também, conter sílica ativa para reduzir a porosidade e melhorar a durabilidade das estruturas confeccionadas com esse material. As dosagens de concreto leve com EPS estudadas foram compostas basicamente por: cimento CPV-ARI, agregado miúdo (areia), pérolas de EPS, água e aditivo superplastificante. Ao final da pesquisa, após análise de 45 misturas, observaram-se ganhos de desempenho mecânico com a adição de sílica ativa, adição de fibras de aço, ajuste na granulometria do agregado miúdo e redução do teor de EPS nas misturas, obtendo-se resistência à compressão na ordem de 16 MPa e massa aparente de 1370 kg/m³, com fator de equivalência (FE) correspondente ou superior ao de um concreto convencional de 20 MPa e 2400 kg/m³. Deve-se ressaltar que o emprego de EPS no concreto reduz o peso dos elementos de construção, estruturais ou não, e o consumo de agregados (areia e brita ou seixo), do mesmo modo que o uso de adições minerais reduz o consumo de cimento. / This study aimed to analyse the lightweight concrete behavior with expanded polystyrene beads (EPS beads) for later use in precast structures made of walls panels and slabs, for example, structures under mechanical actions. Durability parameters and mechanisms of porosity reduction were also considered. Among a universe of requests which structures of lightweight concrete can be submitted, were analysed to different mix designs: compressive strength, modulus of elasticity, water absorption, tensile strength in the splitting and in the flexure tests. EPS beads were incorporate as raw material to provide weight reduction to the concrete. This lightweight concrete can also have silica fume to reduce its porosity and to improve durability of structures made with this material. The lightweight concrete mix designs studied were basically composed by: high initial strength cement, small aggregate (sand), EPS beads, water and superplasticizer additive. At the end of the research, after 45 mixtures analysis, mechanical performance gains were observed with the addition of silica fume, addition of steel fibers, adjusting in the fine aggregate\'s particle size and reducing of EPS content in the mixtures, obtaining compressive strength in the order of 16 MPa and apparent mass of 1370 kg/m³, with equivalence factor (EF) corresponding to or higher than that of an ordinary concrete of 20 MPa and 2400 kg/m³. It should be emphasized that the use of EPS in the concrete reduces the weight of the building members, whether structural or not, and the aggregates consumption (sand and gravel or pebble), in the same way as the employment of mineral additions reduces the consumption of cement.
63

Polímeros extracelulares insolúveis (EPS) nos reatores anaeróbios operados em bateladas seqüenciais: caracterização e fatores que favorecem a produção / Insoluble exopolysaccharides (EPS) in the anaerobic sequential batch biofilm reactor: characterization and factors that enhance the production

Ana Paula Miqueleto 07 November 2006 (has links)
Os exopolissacarídeos (EPS) insolúveis produzidos em processos de tratamento anaeróbios de certos tipos de água residuárias são indesejáveis devido a problemas operacionais que podem vir causar, inviabilizando, muitas vezes, o processo. O reator anaeróbio operado em bateladas seqüenciais contendo biomassa imobilizada (ASBBR) é uma nova configuração de reator que vem sendo estudada no tratamento de águas residuárias cujos resultados são positivos, no entanto em algumas condições observou-se a produção de EPS que inviabilizou o processo. Para evitar estes problemas operacionais em escala real é importante saber os fatores que favorecem a produção de EPS nestes sistemas. Portanto, os objetivos deste trabalho foram verificar a influência de diferentes fontes de carbono e a relação carbono/nitrogênio (C/N), na produção e composição de polímeros extracelulares (EPS) e no desempenho do ASBBR contendo biomassa imobilizada em espuma de poliuretano. As fontes de carbono utilizadas foram glicose, extrato de carne, óleo de soja, as três fontes de carbono juntas, e os ácidos acético, butírico e propiônico juntos. Nos experimentos variando-se a relação C/N utilizou-se glicose como fonte de carbono e uréia como fonte de nitrogênio. As relações C/N foram 13,6 (C/N1), 6,8 (C/N2) e 3,4 (C/N3) gC/gN. Para verificar a influência das condições de microaerofilia na produção do EPS, foi feito também um experimento borbulhando gás nitrogênio, mantendo sob anaerobiose estrita e utilizando glicose como fonte de carbono. Em todos os experimentos o reator foi alimentado com 1000 mgDQO/L. O reator atingiu eficiências médias de remoção da matéria orgânica de 82% em todas as condições, exceto quando o reator foi alimentado com óleo de soja, pois constatou-se o fenômeno de adsorção no material suporte. A produção de EPS por grama de fonte de carbono fornecida foi de 23,6 mg, 13,3 mg, 9,0 mg, 5,9 mg, 5,7 mg, 2,6 mg e 1,4 mg quando o reator foi alimentado com glicose na relação C/N1, óleo de soja, ácidos voláteis, glicose na relação C/N2, glicose/extrato de carne/óleo de soja, glicose na relação C/N3 e extrato de carne, respectivamente. Em condições de anaerobiose estrita não foi observada a produção de EPS. Os resultados sugerem que, a fonte de carbono, condição de microaerofilia e alta relação C/N favorecem a produção de EPS. Por meio de ensaios enzimáticos, com celulase combinada, verificou-se que o principal exopolissacarídeo presente no material polimérico foi celulose. Comparando os espectros de infravermelho das amostras de EPS constatou-se que as diferentes condições nutricionais não influenciaram na composição do polímero. A celulose bacteriana produzida, nesses casos, apresenta organizações alomórficas diferentes quando há glicose no substrato, constatada pelas análises de raios-X. / The insoluble exopolysaccharides (EPS) produced in anaerobic treatment processes from some kinds of wastewater are unwelcome due to operational problems that it may cause, making the process unfeasible most of times. The anaerobic sequential batch biofilm reactor (ASBBR), containing immobilized biomass, is a new configuration of reactor that has been studied for wastewater treatment with positive results. Nevertheless, it was verified the production of EPS in some conditions, which made the process impracticable. To avoid these operational problems in full scale it is important to know the factors that enhance EPS production on those systems. Thus, the objectives of this work were investigating the influence of different carbon sources and the relation carbon/nitrogen (C/N), on the production and composition of extracellular polymers (EPS) and on the performance of the ASBBR with immobilized biomass in polyurethane foam. The carbon sources used were glucose, meat extract, soybean oil, the three carbon sources combined and acetic, butyric and propionic acids combined. On the experiments with variation of C/N relation, glucose was used as carbon source and urea as nitrogen source. The C/N relations were: 13.6 (C/N1), 6.8 (C/N2) and 3.4 (C/N3) gC/gN. Another experiment was accomplished to verify the influence of microerophilic conditions on EPS production, bubbling nitrogen gas, keeping under strict anaerobic conditions and using glucose as carbon source. The reactor was fed with 1000 mgDQO/L in all experiments, achieving 82% of organic substance removal average efficiency, except when fed with soybean oil. At this condition it was verified the adsorption phenomenon in the material support. The yield of EPS was 23.60 mg/g carbon, 13.3 mg/g carbon , 9.0 mg/g carbon, 5.9 mg/g carbon, 5.70 mg/g carbon, 2.6 mg/g carbon and 1.4 mg/g carbon when the reactor was fed with glucose in the relation C/N2, glucose/meat extract/soybean oil, glucose in the relation C/N3 and meat extract, respectively. The production of EPS was not observed at strict anaerobic conditions. Results suggest that the carbon source, microerophilic condition and high C/N relation favor EPS production. Through enzymatic tests with combined cellulase, it was verified that cellulose was the main exopolysaccharide present at the polymeric material. Furthermore, polymers composition is not influenced by different nutritional conditions, comparing infrared spectra of EPS samples. In these cases, the produced bacterial cellulose presents different allomorphic organizations as showed by X-rays analysis.
64

Vliv provedení zateplení administrativní budovy v Blansku na výdaje spojené s jejím provozem / The impact of executing new thermal insulation on an administrative building in Blansko on the expenses associated with its operation

Kopřivová, Petra January 2016 (has links)
The topic of the diploma thesis „ The impact of executing new thermal insulation on an administrative building in Blansko on the expenses associated with its operation“ is a draft and appraisal of four variants of thermal insulation of the building (EPS, EPS G, Mineral wool, Phenolic foam). It deals with an actual building situated in Blansko. All the variants are projected according to the same technical specifications (thermal transmittance) and their thermal parameters, technical parameters and the rate of return have been assessed. The assessed building (The A building) is at rectangular shape. It has six above - ground floors and a basement, it contains mainly administration sites. The construction system is concrete frame, which has curtain wall made of perforated blocks with thickness 250 mm. The building has got reinforced concrete floors, the roofing is made of double-skin roof construction. The supply for heating is a separate gas boiler room.
65

En studie om ESG-betygets effekt på avkastning / A Study Regarding the Effect of the ESG-score on Stock Returns

Bring, Viktor, Jobe, Malcolm January 2021 (has links)
Bakgrund: Den ökade populariteten av ESG som investeringsgrund har gett upphov till en intressant diskussion kring huruvida ESG-betyg har en effekt på avkastning eller inte. En del forskning tar ståndpunkten att en hållbar profil med fokus på ESG påverkar avkastning positivt. De som associerar sig med denna ståndpunkt belyser att investerare kan influera arbete mot en hållbar framtid utan att det ska ge en negativ effekt i önskade avkastningskrav. Däremot finns en motpol i en del av forskningen som hävdar att ESG berör avkastning negativt. Därtill hävdar vissa studier att det finns en diskrepans mellan sektorer på marknaden gällande eventualiteten av ESG:s effekt på riskfyllda tillgångar. Därav är ämnet av intresse med anledning av den motstridiga forskningen angående effekten ESG-betyget har på avkastning.  Syfte: Uppsatsens syfte är att historiskt analysera ESG-betygets eventuella effekt på avkastningen för bolag noterade på OMX Stockholm Large Cap, för att utreda om ESG-betyg kan vara en drivande faktor. Studien har som delsyfte att undersöka om det råder några skillnader i hur ESG-betyget påverkar avkastning i olika sektorer. Metod: Studien har antagit en deduktiv ansats med en kvantitativ metod för att uppfylla syftet. Med grund i dessa metodval analyseras urvalet genom teoretiskt grundade variabler. Studien använder balanserad paneldata som karaktäriseras som kort panel. Resultat: Observerade resultat av rapporten understryker att ESG-betyg återger en försumbar effekt på avkastningen i samtliga regressioner. Koefficienterna för ESG-betygen är dock statistiskt icke-signifikanta. Således kan inte författarna fastställa ESG-betygets inverkan på avkastning för bolagen i urvalet. Däremot finns det tidigare forskning på området som finner liknande resultat som denna studie. / Background: The rising popularity of ESG investing has provided for an interesting deliberation whether the ratio influences stock returns or not. There are those who assert that emphasizing upon ESG yields higher stock returns for investors. Hence, reiterating that investors can contribute to a sustainable future without interfering with desired capital gains. However, there is research that indicates that the incorporation of ESG impedes potential stock returns. Furthermore, previous studies have indicated that there is a potential disparity between sectors of the market, meaning that ESG might have a varied effect. The topic is henceforth of interest due to the contradicting results regarding the effects of ESG on stock returns.  Aim: This study aims to analyze and clarify whether ESG-score is a determining factor in the return of stocks listed on OMX Stockholm Large Cap during the time period 2011-2019. The report will also investigate if there is a difference in its possible impact acrossvarious industries.  Methodology: The study has utilized a deductive and quantitative approach to effectuate the aim of the report. Furthermore, the report has used a balanced panel data with a short panel. Results: The results of the report emphasize that the ESG-score has a negligible effect on stock returns across all industries. However, the coefficients for the ESG-score are statistically insignificant, which means that no conclusion can be established regarding its effect on the selection of stocks listed on OMX Stockholm Large Cap. Nonetheless, there is previous research that supports the findings of the report.
66

Utlandsinvestering, den bättre vägen? : En kvantitativ studie om utlandsinvesteringar och dess påverkan på svenska företag

Amsih, Jouil, Kessidis, Ioannis January 2023 (has links)
Syfte: Syftet är att beskriva och analysera skillnaden mellan företagens finansiella prestation och utländska direktinvesteringar utifrån valda nyckeltal. Metod: Forskningen syftar till att vara objektiv och använda databasen Orbis för att mäta kvantitativa metoder och hålla sig inom den deduktiva ansatsen. Studien bygger också på en totalundersökning eftersom samtliga företag noterade på Nasdaq OMX Stockholms Small-Cap lista var inkluderade i studien. Detta möjliggjorde att slutsatser kunde dras då urvalet är representativt. Studien använder sig av sekundärdata utifrån databasen Orbis. Där en samling av uppgifterna är baserade på en tvärsnittsdesign. Statistisk analys av sekundärdata utfördes i form av deskriptiv statistik, korrelationstester samt Mann-Whitney U-tester. Empiri: Studien påvisar att utländska direktinvesteringar ökar ett företags finansiella prestationer inom variablerna Tobin’s Q, ROA samt helheten av ett företag till en mindre effekt, studien kan inte påvisa någon statistiskt säkerställd skillnad mellan ROE, EPS, EBITDA och utländska direktinvesteringar. Slutsats: Studien visar att utländska direktinvesteringar delvis har en positiv påverkan på de finansiella prestationer ett företag presterar. / Purpose: The purpose is to analyze and describe the difference between companies financial performance and foreign direct investments based on selected key figures. Method: The research aims to be objective, use the database Orbis to measure quantitative methods, and adhere to a deductive approach. The study is also based on a total survey because all companies listed on Nasdaq OMX Stockholm's Small-Cap list were included in the study. This enabled conclusions to be drawn as the sample is representative. The study uses secondary data based on the database Orbis. Where a collection of data is based on a cross-sectional design. Statistical analysis of the secondary data was performed in the form of descriptive statistics, correlation tests, and Mann-Whitney U-tests. Empirical: The study demonstrates that foreign direct investment increases a company's financial performance within the variables Tobin’s Q, ROA, and the whole of a company to a lesser effect, the study cannot demonstrate any statistically significant difference in the relationship between ROE, EPS, EBITDA, and foreign direct investment. Conclusion: The study shows that foreign direct investment positively impacts a company's financial performance.
67

Microbial interactions with soil minerals – effects on extracellular enzyme activity and aggregation

Olagoke, Folasade Kemi 26 October 2022 (has links)
Microorganisms interact with different soil components, such as varying substrates and soil minerals, to drive soil processes and functionality. They can be influenced by the environment, but they themselves can influence their environment by their activities, for example through the production of extracellular enzymes and extracellular polymeric substances (EPS). The formation and stability of aggregates as the backbone of the soil structure, for instance, are thought to be largely influenced by soil microorganisms, or vice versa. There remain, however, open questions as to whether and how microorganisms can influence soil aggregation. While microbes are influencing their environment their interaction with the soil minerals could also change their responses upon adsorption - affecting their influence on soil aggregation. Therefore, the overarching goal of this thesis was to investigate the effect of soil minerals, in particular clay content, on the composition and activity of soil microbial community, with a specific focus on enzyme activities and EPS. Finally, the microbial control of soil aggregation through the influence of substrate availability was explored. In total, two adsorption experiments and two incubation experiments were conducted using soils manipulated experimentally with increasing clay content. The sandy soil was amended with different amounts of soil minerals (i.e. montmorillonite) to achieve a gradient in clay content. For the first incubation experiment, organic substrates differing in decomposability (i.e., starch and cellulose) were added to the soil to stimulate microbial activities and incubated for 80 days. Soil samples from the first incubation experiment were analysed after 0, 3, 10, 20, 40 and 80 days for enzyme activities, microbial community composition, biomass C, EPS-protein and polysaccharide. Additionally, the geometric mean diameter and mean weight diameter of the soil aggregates were determined as measures of aggregate formation and stability, respectively. The first adsorption experiment examined the effect of soil mineral phases on the activities of extracellular enzymes using commercially available extracellular enzymes (α-glucosidase) added to the soil. The second adsorption and incubation experiment investigated the persistence of extracellular enzyme activities (commercially available α-amylase and cellulase) affected by soil minerals. For further insight into how other soil minerals affect extracellular enzymes, kaolinite and goethite in addition to montmorillonite were included in the second adsorption and incubation experiment. The prepared complexes (enzyme + soil and/or soil minerals) from the second adsorption experiment were incubated for 100 days. Further analytical methods include the determination of enzyme activities, microbial biomass C, extraction and quantification of the soil EPS, protein analyses, DNA isolation, DGGE, qPCR and Illumina sequencing. The adsorption experiment showed that extracellular enzyme activities decreased with increasing clay contents. In contrast, such an inhibitory effect on microbial enzyme activity was only observed directly in the incubation experiment after the stimulation of in-situ microorganisms for extracellular enzyme production through substrate addition. Higher extracellular enzyme activities at later incubation days in soils with high clay content suggested an adaptation of the microbial community in response to soil clay content and/ or persistence of extracellular enzymes by adsorption to mineral surfaces. However, the second adsorption experiment showed that the high specific activity and persistence of the enzymes were constrained by the availability of sorption sites. It is therefore reasonable to assume that soil mineral phases support microorganisms in less-sorptive environments by sparing energy on enzyme production, since even a small enzyme release could already propel sufficient activities to degrade target carbon substrates. Starch amendment accelerated respiration and microbial biomass much more than cellulose. While microbial community differed depending on the C substrate (starch or cellulose) added, clay addition had a stronger influence on alpha diversity than substrate addition. Although the production of EPS-protein was closely linked to the provision of additional substrates, the addition of clay minerals resulted in more EPS production than when no additional clay was present. By correlating soil aggregation (stability and formation) with the recorded microbial parameters (that is biomass C, EPS-protein and EPS-polysaccharide), both EPS-protein and EPS-polysaccharide exhibited a significant control on aggregate formation and microbial processes, though, surprisingly, more strongly with high clay content. It was observed that EPS is only a transient compound, which initiates aggregate formation, but clay content plays a more significant role in long-term aggregate stabilization. Overall, this thesis contributed to our knowledge about the interaction of microorganisms with the soil mineral phase and their influence on soil structural stability. The findings established that soil minerals shape the composition and activity of microbial communities. In turn, the microbial production of EPS seems to be more significant for aggregate formation than stability. The results on the effect of soil minerals on extracellular activities provided a paradigm that the persistence of enzyme activities by adsorption does not always hold. Producing EPS might contribute to microbial adaptation that mitigates the negative effect of adsorption on extracellular enzymes. It might also be probable that the EPS become a substance of degradation for the extracellular enzymes. Overall, the results indicated that in clay-rich soils the process leading to extracellular enzyme persistence can be stochastic, depending on multiple factors including sorption sites and substrate availability. Labile organic C clearly plays a role in aggregate formation by supporting EPS production. However, increasing clay content enhanced aggregate stability, promoted the development of distinct microbial communities and increased EPS production. The discrepancy so observed in the contribution of the two EPS parameters, EPS polysaccharide and protein, on soil aggregation points to the need for inclusion of different EPS compositions in future studies relating to soil aggregation.
68

Adoption of Sustainable Packaging Solutions for the Fish Industry : A case study on a corrugated cardboard packaging solution for fresh fish / Adoption av Hållbara Förpackningslösningar för Fiskindustrin : En fallstudie på en wellpapp förpackningslösning för färsk fisk

Kopp, Andreas, Falconer, Robin January 2020 (has links)
The rapid development of plastic production the last couple of decades has led to extensive use of plastic products and vast problems with littering, waste management and exploitation of natural resources. Due to the cheap and easy production of plastics, the world’s population has extended the limit of acceptable usage. The world’s oceans are filled with plastic debris and waste is landfilled, which have had large impacts on the ecosystem, animal and human life (World Environment Day Outlook, 2018). One of the industries that have been revolutionised by the development of plastic advancement is the packaging industry, where products can be protected and quality can be kept, helping globalisation and developing the modern economy (UNEP, 2018). However, due to the lack of waste management systems and recycling facilities for plastics, the world’s population is demanding change. The United Nations have developed the Sustainability Goals and issued The New Plastics Economy, where governments, citizens and regulatory institutions are to work towards a circular economy (The New Plastics Economy, 2019). The demands are addressed towards whole value chains, from production to end-use, and include waste minimising, material optimisation, increase of recyclability, and the development of sustainable alternatives. The fish industry has historically been limited to a few packaging options and expanded polystyrene (EPS) has been the least inferior one when packaging fresh fish for transportation and keeping the quality of the fish. EPS has great material properties for this purpose, however, with the sustainability transition and increasing demands from consumers, the material is regarded as unsustainable with limited availability and profitability to recycle (Hansen et al., 2012). This master thesis aims to investigate if there are sustainable packaging solutions for fresh fish and how these could be adopted by the fish industry. This was done by conducting a qualitative case study on an alternative packaging solution made from corrugated cardboard. Stakeholders from the whole fish value chain were interviewed in order to understand the value perception of existing and alternative packaging solutions for fresh fish. The findings have been analysed using innovation adoption theory together with a sustainability framework. This in order to understand the adoption behaviour of innovative sustainable packaging solutions, and the sustainability impact of these with regards to environmental, social and economic aspects. The study has identified two packaging solutions, develop recycling systems for EPS and fish boxes made from corrugated cardboard, that the fish industry should consider adopting. The two identified packaging solutions have different diffusion possibilities, where the corrugated cardboard fish box is considered as the most sustainable solution. / Den snabba utvecklingen av plastproduktion de senaste decennierna har lett till en omfattande användning av plastprodukter, vilket har medfört problem som nedskräpning, ökad avfallshantering och överdriven användning av naturresurser. På grund av billig och enkel tillverkning av plast har världens befolkning överskridit gränsen för acceptabel användning. Världens hav är fyllda med spillror av plast och avfall deponeras, vilket har haft stora effekter på ekosystemet och djur- och människoliv (World Environment Day Outlook, 2018). En av branscherna som har revolutionerats av utvecklingen av plast är förpackningsindustrin, där plasten bidrar till att produkter kan skyddas och kvalitet kan bevaras, vilket har hjälpt globaliseringen och utvecklat den moderna ekonomin (UNEP, 2018). På grund av bristen på avfallshanteringssystem och återvinningsanläggningar för plast kräver dock världens befolkning förändring. FN har utvecklat hållbarhetsmål och utfärdat The New Plastics Economy, där regeringar, människor och tillsynsinstitutioner ska arbeta för en cirkulär ekonomi (The New Plastics Economy, 2019). Kraven riktas mot hela värdekedjor, från produktion till slutanvändning, och inkluderar avfallsminimering, materialoptimering, ökad återvinningsbarhet och utveckling av hållbara alternativ. Fiskindustrin har historiskt sett varit begränsad till att använda materialet expanderad polystyren (EPS) vid förpackning av färsk fisk för transport och för att behålla fiskens kvalitet. Detta material har bra materialegenskaper för dessa ändamål, men med hållbarhetsövergången och ökade krav från konsumenter anses materialet vara ohållbart med begränsad tillgänglighet och lönsamhet att återvinna (Hansen et al., 2012). Denna masteruppsats syftar till att undersöka om det finns hållbara förpackningslösningar för färsk fisk och hur dessa bör anammas av fiskindustrin. Detta gjordes genom att genomföra en kvalitativ fallstudie av en alternativ förpackningslösning gjord av wellpapp. Intressenter från fiskens hela värdekedja intervjuades för att förstå värdesynen på befintliga och alternativa förpackningslösningar för färsk fisk. Resultaten har analyserats med hjälp av innovations teori, tillsammans med ett hållbarhetsramverk. Detta för att förstå adoptionsbeteendet för innovativa hållbara förpackningslösningar och hållbarhetspåverkan av dessa när det gäller miljö, samt sociala och ekonomiska aspekter. Studien har identifierat två förpackningslösningar; ett utvecklat återvinningssystem för EPS och fisklådor tillverkade av wellpapp, som fiskindustrin bör överväga att anamma. De två identifierade lösningarna har olika diffusionsmöjligheter, där wellpappfisklåda betraktas som den mest hållbara lösningen.
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Modelo de seguridad de la información para contribuir en la gestión de entidades de servicios de saneamiento del norte peruano

Navarro Reyes, Alejandro Javier January 2024 (has links)
El trabajo de investigación realizado, se focaliza en la exigencia de gestionar adecuadamente la Seguridad de la Información (en adelante SI) en las Entidades Prestadoras de Servicios de Saneamiento (EPS) del norte peruano, detectada luego del diagnóstico aplicado a una muestra de cuatro entidades del sector, donde se demostró que carecen de instrumentos para su gestión con el fin de asegurar la disponibilidad, integridad y confidencialidad de sus activos de información, además de no contar con estructuras (roles y áreas) que den soporte a la gestión de la SI. El objetivo general planteado fue proponer un modelo de SI basado en marcos de trabajo y estándares relacionados con la SI, para contribuir en la gestión de las EPS del norte peruano. El trabajo de investigación realizado es de tipo propositiva y descriptiva, de diseño no experimental. El contenido del modelo de SI propuesto se validó por juicio de expertos, logrando su aceptación, lo cual le permite ser aplicado en otras EPS del norte peruano. Asimismo, se comprobó la validez de la pertinencia del modelo de SI propuesto al aplicarse como caso de estudio en la Entidad Prestadora de Servicios de Saneamiento de Lambayeque (EPSEL S.A.), logrando identificar 165 riesgos, de los cuales se observó que existen 31 riesgos de magnitud extrema y 30 riesgos de magnitud alta, a los que se aplicaron 15 controles de seguridad, que fueron monitoreados para estimar su grado de cumplimiento, estableciéndose un plan de mejora continua con los 10 controles que cumplen parcialmente su desempeño. / The research work carried out focuses on the requirement to adequately manage Information Security (hereinafter SI) in the Sanitation Service Providing Entities (EPS) in northern Peru, detected after the diagnosis applied to a sample of four entities. of the sector, where it was demonstrated that they lack instruments for their management in order to ensure the availability, integrity and confidentiality of their information assets, in addition to not having structures (roles and areas) that support the management of the IS. . The general objective set was to propose an IS model based on frameworks and standards related to the IS, to contribute to the management of the EPS in northern Peru. The research work carried out is of a purposeful and descriptive type, with a non-experimental design. The content of the proposed IS model was validated by expert judgment, achieving its acceptance, which allows it to be applied in other EPSs in northern Peru. Likewise, the validity of the relevance of the proposed IS model was verified when applied as a case study in the Lambayeque Sanitation Services Provider Entity (EPSEL S.A.), managing to identify 165 risks, of which it was observed that there are 31 risks of extreme magnitude and 30 high magnitude risks, to which 15 security controls were applied, which were monitored to estimate their degree of compliance, establishing a continuous improvement plan with the 10 controls that partially comply with their performance.
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Modelling and simulation of membrane bioreactors for wastewater treatment

Janus, Tomasz January 2013 (has links)
The work presented in this thesis leads to the formulation of a dynamic mathematical model of an immersed membrane bioreactor (iMBR) for wastewater treatment. This thesis is organised into three parts, each one describing a different set of tasks associated with model development and simulation. In the first part, the Author qualitatively and quantitatively compares various published activated sludge models, i.e. models of biochemical processes associated with bacterial growth, decay, lysis and substrate utilisation in activated sludge systems. As the thesis is focused on modelling membrane bioreactors (MBRs) which are known to experience membrane fouling as a result of adsorption of biopolymers present in the bulk liquid onto and within the membrane, all activated sludge models considered in this thesis are able to predict, with various levels of accuracy, the concentrations of biopolymeric substances, namely soluble microbial products (SMP) and extracellular polymeric substances (EPS). Some of the published activated sludge models dedicated to modelling SMP and EPS kinetics in MBR systems were unable to predict the SMP and EPS concentrations with adequate levels of accuracy, without compromising the predictions of other sludge and wastewater constituents. In other cases, the model equations and the assumptions made by their authors were questionable. Hence, two new activated sludge models with SMP and EPS as additional components have been formulated, described, and simulated. The first model is based on the Activated Sludge Model No. 1 (ASM1) whereas the second model is based on the Activated Sludge Model No. 3 (ASM3). Both models are calibrated on two sets of data obtained from a laboratory-scale system and a full-scale system and prove to be in very good agreement with the measurements. The second part of this thesis explains the development of two membrane fouling models. These models are set to describe the loss of membrane permeability during filtration of various solutions and suspensions. The main emphasis is placed on filtration of activated sludge mixtures, however the models are designed to be as general as feasibly possible. As fouling is found to be caused by a large number of often very complex processes which occur at different spatial as well as temporal scales, the two fouling models developed here have to consider a number of significant simplifications and assumptions. These simplifications are required to balance the model's accuracy, generality and completeness with its usability in terms of execution times, identifiability of parameters and ease of implementation in general purpose simulators. These requirements are necessary to ascertain that long term simulations as well as optimisation and sensitivity studies performed in this thesis either individually on fouling models or on the complete model of a MBR can be carried out within realistic time-scales. The first fouling model is based on an idea that fouling can be subdivided into just two processes: short-term reversible fouling and long-term irreversible fouling. These two processes are described with two first order ordinary differential equations (ODEs). Whilst the first model characterises the membrane filtration process from an observer's input-output point of view without any rigorous deterministic description of the underlying mechanisms of membrane fouling, the second model provides a more theoretical and in-depth description of membrane fouling by incorporating and combining three classical macroscopic mechanistic fouling equations within a single simulation framework. Both models are calibrated on a number of experimental data and show good levels of accuracy for their designated applications and within the intended ranges of operating conditions. In the third part, the first developed biological model (CES-ASM1) is combined with the behavioural fouling model and the links between these two models are formulated to allow complete simulation of a hollow fibre (HF) immersed membrane bioreactor (iMBR). It is assumed that biological processes affect the membrane through production of mixed liquor suspended solids (MLSS), SMP and EPS which cause pore blockage, cake formation, pore diameter constriction, and affect the specific cake resistance (SCR). The membrane, on the other hand, has a direct effect on the bulk liquid SMP concentration due to its SMP rejection properties. SMP are assumed to be solely responsible for irreversible fouling, MLSS is directly linked to the amount of cake depositing on the membrane surface, whereas EPS content in activated sludge affects the cake's SCR. Other links provided in the integrated MBR model include the effects of air scouring on the rate of particle back-transport from the membrane surface and the effects of MLSS concentration on oxygen mass transfer. Although backwashing is not described in great detail, its effects are represented in the model by resetting the initial condition in the cake deposition equation after each backwash period. The MBR model was implemented in Simulink® using the plant layout adopted in the MBR benchmark model of Maere et al. [160]. The model was then simulated with the inputs and operational parameters defined in [36, 160]. The results were compared against the MBR benchmark model of Maere et al. [160] which, contrary to this work, does not take into account the production of biopolymers, the membrane fouling, nor any interactions between the biological and the membrane parts of an MBR system.

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