993 resultados para Oxygen cost


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Objective: to describe and evaluate the acceptance of a low-cost chest tube insertion porcine model in a medical education project in the southwest of Paraná, Brazil. Methods: we developed a low-cost and low technology porcine model for teaching chest tube insertion and used it in a teaching project. Medical trainees - students and residents - received theoretical instructions about the procedure and performed thoracic drainage in this porcine model. After performing the procedure, the participants filled a feedback questionnaire about the proposed experimental model. This study presents the model and analyzes the questionnaire responses. Results: seventy-nine medical trainees used and evaluated the model. The anatomical correlation between the porcine model and human anatomy was considered high and averaged 8.1±1.0 among trainees. All study participants approved the low-cost porcine model for chest tube insertion. Conclusion: the presented low-cost porcine model for chest tube insertion training was feasible and had good acceptability among trainees. This model has potential use as a teaching tool in medical education.

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In this thesis, a model called CFB3D is validated for oxygen combustion in circulating fluidized bed boiler. The first part of the work consists of literature review in which circulating fluidized bed and oxygen combustion technologies are studied. In addition, the modeling of circulating fluidized bed furnaces is discussed and currently available industrial scale three-dimensional furnace models are presented. The main features of CFB3D model are presented along with the theories and equations related to the model parameters used in this work. The second part of this work consists of the actual research and modeling work including measurements, model setup, and modeling results. The objectives of this thesis is to study how well CFB3D model works with oxygen combustion compared to air combustion in circulating fluidized bed boiler and what model parameters need to be adjusted when changing from air to oxygen combustion. The study is performed by modeling two air combustion cases and two oxygen combustion cases with comparable boiler loads. The cases are measured at Ciuden 30 MWth Flexi-Burn demonstration plant in April 2012. The modeled furnace temperatures match with the measurements as well in oxygen combustion cases as in air combustion cases but the modeled gas concentrations differ from the measurements clearly more in oxygen combustion cases. However, the same model parameters are optimal for both air and oxygen combustion cases. When the boiler load is changed, some combustion and heat transfer related model parameters need to be adjusted. To improve the accuracy of modeling results, better flow dynamics model should be developed in the CFB3D model. Additionally, more measurements are needed from the lower furnace to find the best model parameters for each case. The validation work needs to be continued in order to improve the modeling results and model predictability.

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In this work the implementation of the active magnetic bearing control system in a single FPGA is studied. Requirements for the full magnetic bearing control system are reviewed. Different control methods for active magnetic bearings are described shortly. Flux and the current base controllers are implemented in a FPGA. Suitability of the con-trollers for a low-cost magnetic bearing application is studied. Floating-point arithmetic’s are used in the controllers to ease designing burden and improve calculation precision. Per-formance of the flux controller is verified with simulations.

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Chronic inflammation is the underlying cause of many common disabling conditions such as rheumatoid arthritis (RA), multiple sclerosis, coeliac disease, type I diabetes and coronary artery disease. NOX2 complex derived reactive oxygen species (ROS) are known to regulate joint inflammation in rats and mice, and additionally recent genetic evidence associates phagocyte ROS and the development RA in humans. Ncf1mutated mice have lost the functionality of their NOX2 complex and thus have no phagocyte ROS production. These mice suffer from exacerbated arthritis. The immune suppressive effect of the NOX2 complex derived ROS is mediated by monocytes/macrophages that downregulate the activation of autoreactive T cells. The aim of this thesis was to study how ROS modulate immune responses in different arthritis models and in tumor development. Additionally, genome wide gene expression profiling was carried out to assess the global effects of NOX2 complex derived ROS. Firstly, these results confirmed the potent anti-inflammatory nature of phagocyte ROS in arthritis models that were driven by the adaptive immune system. Secondly, arthritis models with predominantly innate immunity induced pathophysiology were moderately enhanced by phagocyte, more specifically, neutrophil derived ROS. Thirdly, the ROS induced immune suppression mediated by the adaptive immune system allowed development of bigger implanted tumors, while phagocyte ROS production did not affect the development of spontaneously growing tumors. Lastly, genome wide gene expression analysis revealed that both humans and mice with abrogated phagocyte NOX2 complex ROS production had an enhanced type I interferon signature in blood, reflecting their hyperinflammatory immune status.

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The target organization of this study, otherwise South-Karelia Social and Health Care District (Eksote) provides health, senior, family and social welfare services. South Karelia Central Hospital provides special health care and offers health services from all of the most important medical specialties. Eksote has in use 15D instrument to measure the health-related quality of life (HRQoL) of their patients before and after their interventions for observing the health effects of the medical care. Furthermore, 15D allows measuring the effectiveness and cost-effectiveness of health care when comparing these before and after results of the 15D measurements and adding the costs of the interventions into this research. The main purposes of this study were to analyze the effectiveness and cost-effectiveness of medical care in South Karelia Central Hospital by using the gathered 15D data to calculate effectiveness and cost-effectiveness ratios and to analyze the reliability and availability of the data. Study has been conducted using literature review and quantitative research methods. The results indicate that from the patients within the eight units selected to this study the 15D change information was available from the 52 %, the 15D change and the cost information from 38 % and the information of quality-adjusted life years (QALYs) produced and the cost information from 35 %. The effectiveness and cost-effectiveness of medical care were greatest at the units of Pain Outpatient Clinic and Rheumatic Diseases Outpatient Clinic. The most effective medical care is given in the unit where the average price of one produced QALY is the highest (Orthopedics). However, the calculated standard deviations pointed out that there are great variances in the effectiveness and cost-effectiveness within the units also.

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Blood-derived products are commonly administered to horses and humans to treat many musculoskeletal diseases, due to their potential antioxidant and anti-inflammatory effects. Nevertheless, antioxidant effects have never been shown upon horse synovial fluid cells in vitro. If proved, this could give a new perspective to justify the clinical application of blood-derived products. The aim of the present study was to investigate the antioxidant effects of two blood-derived products - plasma (unconditioned blood product - UBP) and a commercial blood preparation (conditioned blood product - CBP)¹ - upon stimulated equine synovial fluid cells. Healthy tarsocrural joints (60) were tapped to obtain synovial fluid cells; these cells were pooled, processed, stimulated with lipopolysaccharide (LPS) or phorbol 12-myristate 13-acetate (PMA), and evaluated by flow cytometry for the production of reactive oxygen species (ROS). Upon addition of any blood-derived product here used - UBP and CBP - there was a significant decrease in the oxidative burst of synovial fluid cells (P<0.05). There was no difference between UBP and CBP effects. In conclusion, treatment of stimulated equine synovial cells with either UBP or CBP efficiently restored their redox equilibrium.

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The aim of this work was to propose, apply and evaluate a methodical approach to select welding processes in a productive environment based on market requirements of Quality and Costs. A case study was used. The welds were carried out in laboratory, simulating the joint conditions of a manufacturer and using several welding processes: SMAW, GTAW, pulsed GTAW, GMAW with CO2 and Ar based shielding gases and pulsed GMAW. For Quality analysis geometrical aspects of the beads were considered and for Cost analysis, welding parameters and consumable prices. Quantitative indices were proposed and evaluated. After that, evaluation of both Quality and Costs was done, showing to be possible to select the most suitable welding process to a specific application, taking into account the market conditions of a company.

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Advanced oxidation processes (AOPs) have been studied and developed to suffice the effective removal of refractory and toxic compounds in polluted water. The quality and cost of wastewater treatment need improvements, and electric discharge technology has a potential to make a significant difference compared to other established AOPs based on energy efficiency. The generation of active oxidant species such as ozone and hydroxyl radicals by high voltage discharge is a relatively new technology for water treatment. Gas-phase pulsed corona discharge (PCD), where a treated aqueous solution is dispersed between corona-producing electrodes free of the dielectric barriers, was developed as an alternative approach to the problem. The short living radicals and ozone formed in the gas phase and at the gas-liquid interface react with dissolved impurities. PCD equipment has a relatively simple configuration, and with the reactor in an enclosed compartment, it is insensitive towards gas humidity and does not need the gas transport. In this thesis, PCD was used to study and evaluate the energy efficiency for degrading various organic compounds, as well as the chemistry of the oxidation products formed. The experiments investigate the aqueous oxidation of phenol, humic substances, pharmaceutical compounds (paracetamol, ibuprofen, indomethacin, salicylic acids, -estradiol), as well as lignin degradation and transformation to aldehydes. The study aims to establish the influence of initial concentration of the target pollutant, the pulsed discharge parameters, gas phase composition and the pH on the oxidation kinetics and the efficiency. Analytical methods to measure the concentrations of the target compounds and their by-products include HPLC, spectrophotometry, TOC and capillary electrophoresis. The results of the research included in this summary are presented in the attached publications and manuscripts accepted for publication. Pulsed corona discharge proved to be highly effective in oxidizing each of the target compounds, surpassing the closest competitor, conventional ozonation. The increase in oxidation efficiencies for some compounds in oxygen media and at lower pulse repetition frequencies shows a significant role of ozone. The role of the ·OH radicals was established in the surface reactions. The main oxidation products, formation of nitrates, and the lignin transformation were quantified. A compound specific approach is suggested for optimization of the PCD parameters that have the most significant impact on the oxidation energy efficiency because of the different characteristics and responses of the target compound to the oxidants, as well as different admixtures that are present in the wastewater. Further studies in the method’s safety (nitration and nitrosation of organic compounds, nitrite and nitrate formation enhancement) are needed for promoting the method.

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Lahti Energia Oy:n kivihiiltä polttavan Kymijärvi I voimalaitoksen vuotuiset käyttötunnit ovat vähentyneet. Syy vähennykseen on ollut uuden kaasutusvoimalaitoksen käyttöönotto vuonna 2012, jolloin vanhan voimalaitoksen käytölle ei ole ollut tarvetta kesäkuukausina. Seisonta-aikana voimalaitoksen höyryvoimaprosessi tulee säilöä. Säilönnällä tarkoitetaan toimenpiteitä, joilla estetään korroosio-olosuhteiden syntyminen voimalaitoksen laitteisiin. Säilöntätavasta riippuen estetään joko hapen tai kosteuden esiintyminen. Tässä diplomityössä tutkitaan eri säilöntämenetelmien ominaisuuksia tavoitteena löytää sopivin vaihtoehto vanhalle kivihiilivoimalaitokselle. Työssä perehdytään teorian kautta kolmeen menetelmään voimalaitoksen kattilan säilönnässä. Typpi- ja märkäsäilönnässä estetään hapen ja kuivailmasäilönnässä kosteuden esiintyminen. Työssä on myös tutkittu kattilan säilöntämenetelmien vaikutuksia muihin laitteistoihin ja järjestelmiin. Tuloksien perusteella voidaan todeta, että kuivailmasäilöntä on toimivin ratkaisu voimalaitoksen viimeisille käyttövuosille. Voimalaitoksen jäädessä varavoimalaitokseksi on typpisäilöntä kustannustehokkain vaihtoehto.

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Maritime safety is an issue that has gained a lot of attention in the Baltic Sea area due to the dense maritime traffic and transportation of oil in the area. Lots of effort has been paid to enhance maritime safety in the area. The risk exists that excessive legislation and other requirements mean more costs for limited benefit. In order to utilize both public and private resources efficiently, awareness is required of what kind of costs maritime safety policy instruments cause and whether the costs are in relation to benefits. The aim of this report is to present an overview of the cost-effectiveness of maritime safety policy instruments focusing on the cost aspect: what kind of costs maritime safety policy causes, to whom, what affects the cost-effectiveness and how cost-effectiveness is studied. The study is based on a literature review and on the interviews of Finnish maritime experts. The results of this study imply that cost-effectiveness is a complicated issue to evaluate. There are no uniform practices for which costs and benefits should be included in the evaluation and how they should be valued. One of the challenges is how to measure costs and benefits during the course of a longer time period. Often a lack of data erodes the reliability of evaluation. In the prevention of maritime accidents, costs typically include investments in ship structures or equipment, as well as maintenance and labor costs. Also large investments may be justifiable if they respectively provide significant improvements to maritime safety. Measures are cost-effective only if they are implemented properly. Costeffectiveness is decreased if a measure causes overlapping or repetitious work. Costeffectiveness is also decreased if the technology isn’t user-friendly or if it is soon replaced with a new technology or another new appliance. In future studies on the cost-effectiveness of maritime safety policy, it is important to acknowledge the dependency between different policy instruments and the uncertainty of the factors affecting cost-effectiveness. The costs of a single measure are rarely relatively significant and the effect of each measure on safety tends to be positive. The challenge is to rank the measures and to find the most effective combination of different policy instruments. The greatest potential offered for the analysis of cost-effectiveness of individual measures is their implementation in clearly defined risk situations, in which different measures are truly alternative to each other. Overall, maritime safety measures do not seem to be considered burdening for the shipping industry in Finland at the moment. Generally actors in the Finnish shipping industry seem to find maintaining a high safety level important and act accordingly.

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Tämä työ tehtiin Kone Industrial Oy:lle Major Projects yksikköön, laatuosastolle. Kone Major Projects yksikkö keskittyy erikoisiin ja suuriin hissi- ja liukuporras projekteihin. Työn tavoitteena oli luoda harmonisoitu prosessi hissikomponenttien laaduntarkkailua varten sekä tarkastella ja vertailla kustannussäästöjä, jota tällä uudella prosessilla voidaan saavuttaa. Tavoitteena oli saavuttaa 80-prosentin kustannussäästöt laatukustannuksissa uuden laatuprosessin avulla. Työn taustana ja tutkimusongelmana ovat lisääntyneet erikoisprojektit ja niiden myötä lisääntynyt laaduntarkkailun tarve. Ongelmana laaduntarkkailussa voitiin pitää harmonisoidun ja selkeän prosessin puuttumista C-prosessikomponenttien valmistuksessa. Lisäksi kehitysprosessin aikana luotiin vanhojen työkalujen pohjalta keskeinen laaduntarkkailutyökalu, CTQ-työkalu. Työssä käsitellään ensin Konetta yhtiönä ja selvitetään Koneen keskeisimmät prosessit työn taustaksi. Teoria osuudessa käsitellään prosessin kehitykseen liittyviä teorioita sekä yleisiä laatukäsitteitä ja esitetään teorioita laadun asemasta nykypäivänä. Lopuksi käsitellään COQ eli laatukustannusten teoriaa ja esitellään teoria PAF-analyysille, jota käytetään työssä laatukustannusten vertailuun case esimerkin avulla. Työssä kuvataan CTQ prosessin luominen alusta loppuun ja case esimerkin avulla testataan uutta CTQ prosessia pilottihankkeessa. Tässä case esimerkissä projektin bracket eli johdekiinnitysklipsi tuotetaan uuden laatuprosessin avulla sekä tehdään kustannusvertailu saman projektin toisen bracketin kanssa, joka on tuotettu ennen uuden laatuprosessin implementoimista. Työn lopputuloksena CTQ prosessi saatiin luotua ja sitä pystyttiin testaamaan käytännössä case esimerkin avulla. Tulosten perusteella voidaan sanoa, että CTQ prosessin käyttö vähentää laatukustannuksia huomattavasti ja helpottaa laadunhallintaa C-prosessikomponenttien tuotannossa.

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In today's logistics environment, there is a tremendous need for accurate cost information and cost allocation. Companies searching for the proper solution often come across with activity-based costing (ABC) or one of its variations which utilizes cost drivers to allocate the costs of activities to cost objects. In order to allocate the costs accurately and reliably, the selection of appropriate cost drivers is essential in order to get the benefits of the costing system. The purpose of this study is to validate the transportation cost drivers of a Finnish wholesaler company and ultimately select the best possible driver alternatives for the company. The use of cost driver combinations as an alternative is also studied. The study is conducted as a part of case company's applied ABC-project using the statistical research as the main research method supported by a theoretical, literature based method. The main research tools featured in the study include simple and multiple regression analyses, which together with the literature and observations based practicality analysis forms the basis for the advanced methods. The results suggest that the most appropriate cost driver alternatives are the delivery drops and internal delivery weight. The possibility of using cost driver combinations is not suggested as their use doesn't provide substantially better results while increasing the measurement costs, complexity and load of use at the same time. The use of internal freight cost drivers is also questionable as the results indicate weakening trend in the cost allocation capabilities towards the end of the period. Therefore more research towards internal freight cost drivers should be conducted before taking them in use.