1000 resultados para Environmental vibration


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Ympäristötekniikan kandidaatin ja diplomi-insinöörin tutkinto-ohjelmien itsearviointiraportissa käsitellään tutkinto-ohjelmien osaamistavoitteita ja niiden saavuttamista. Raportissa käydään läpi myös käytössä olevat resurssit sekä tutkinto-ohjelmiin liittyviä tunnuslukuja. Itsearviointi on toteutettu kansainvälisen akkreditointijärjestön kriteerien mukaisesti (ASIIN ja EUR-ACE).

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The purpose of this study is to identify successful capabilities that Finnish SME’s, in the environmental technology industry, use in their internationalization efforts. It is the goal of this study to create a list of guidelines and capabilities that other SME’s in this industry can use to help be more effective in their internationalization efforts. Through a study of three Finnish SME’s, in the growing environmental technologies sector, several common internationalization capabilities were identified to be helpful in their internationalization process. The common capabilities that were identified were then categorized together to show not only what capabilities were identified but if they came from firm, location or network specific advantages. As a result of the study, three dynamic capabilities were formulated as guidelines. These guidelines are designed so that a SME based in Finland, and in the environmental technology industry, could use them to help them in their own internationalization process.

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Environmental accountability has become a major source of competitive advantage for industrial companies, because customers consider it as relevant buying criterion. However, in order to leverage their environmental responsibility, industrial suppliers have to be able to demonstrate the environmental value of their products and services, which is also the aim of Kemira, a global water chemistry company considered in this study. The aim of this thesis is to develop a tool which Kemira can use to assess the environmental value of their solutions for the customer companies in mining industry. This study answers to questions on what kinds of methods to assess environmental impacts exist, and what kind of tool could be used to assess the environmental value of Kemira’s water treatment solutions. The environmental impacts of mining activities vary greatly between different mines. Generally the major impacts include the water related issues and wastes. Energy consumption is also a significant environmental aspect. Water related issues include water consumption and impacts in water quality. There are several methods to assess environmental impacts, for example life cycle assessment, eco-efficiency tools, footprint calculations and process simulation. In addition the corresponding financial value may be estimated utilizing monetary assessment methods. Some of the industrial companies considered in the analysis of industry best practices use environmental and sustainability assessments. Based on the theoretical research and conducted interviews, an Excel based tool utilizing reference data on previous customer cases and customer specific test results was considered to be most suitable to assess the environmental value of Kemira’s solutions. The tool can be used to demonstrate the functionality of Kemira’s solutions in customers’ processes, their impacts in other process parameters and their environmental and financial aspects. In the future, the tool may be applied to fit also Kemira’s other segments, not only mining industry.

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The purpose of the thesis is to give an overview of the cleantech sector and to give an answer how cleantech companies can evaluate the environmental sustainability of their business by utilizing various indicators and measures. The thesis is a literature study and it is based on a secondary data. Thesis presents the definitions to cleantech as well as its history and the main industries. Cleantech market overview in Finland and worldwide is also introduced. Furthermore, various indicators are presented in order to evaluate the environmental sustainability of companies' business. In the end, indicators used in cleantech sector are evaluated. As a result, the thesis presents the following methodologies that can be used in evaluating the environmental sustainability in the cleantech sector: Sustainability assessment framework, Environmental value analysis, COMPLIMENT - Environmental performance index for industries and Environmental assessment for cleaner production. More tools are still needed to evaluate environmental sustainability in the cleantech sector.

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The Pasvik monitoring programme was created in 2006 as a result of the trilateral cooperation, and with the intention of following changes in the environment under variable pollution levels. Water quality is one of the basic elements of the Programme when assessing the effects of the emissions from the Pechenganikel mining and metallurgical industry (Kola GMK). The Metallurgic Production Renovation Programme was implemented by OJSC Kola GMK to reduce emissions of sulphur and heavy metal concentrated dust. However, the expectations for the reduction in emissions from the smelter in the settlement Nikel were not realized. Nevertheless, Kola GMK has found that the modernization programme’s measures do not provide the planned reductions of sulfur dioxide emissions. In this report, temporal trends in water chemistry during 2000–2009 are examined on the basis of the data gathered from Lake Inari, River Pasvik and directly connected lakes, as well as from 26 small lakes in three areas: Pechenganikel (Russia), Jarfjord (Norway) and Vätsäri (Finland). The lower parts of the Pasvik watercourse are impacted by both atmospheric pollution and direct wastewater discharge from the Pechenganikel smelter and the settlement of Nikel. The upper section of the watercourse, and the small lakes and streams which are not directly linked to the Pasvik watercourse, only receive atmospheric pollution. The data obtained confirms the ongoing pollution of the river and water system. Copper (Cu), nickel (Ni) and sulphates are the main pollution components. The highest levels were observed close to the smelters. The most polluted water source of the basin is the River Kolosjoki, as it directly receives the sewage discharge from the smelters and the stream connecting the Lakes Salmijarvi and Kuetsjarvi. The concentrations of metals and sulphates in the River Pasvik are higher downstream from the Kuetsjarvi Lake. There has been no fall in the concentrations of pollutants in Pasvik watercourse over the last 10 years. Ongoing recovery from acidification has been evident in the small lakes of the Jarfjord and Vätsäri areas during the 2000s. The buffering capacity of these lakes has improved and the pH has increased. The reason for this recovery is that sulphate deposition has decreased, which is also evident in the water quality. However, concentrations of some metals, especially Ni and Cu, have risen during the 2000s. Ni concentrations have increased in all three areas, and Cu concentrations in the Pechenganickel and Jarfjord areas, which are located closer to the smelters. Emission levels of Ni and Cu did not fall during 2000s. In fact, the emission levels of Ni compounds even increased compared to the 1990s.

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This thesis focuses on collaborative activities with regard to environmental issues both within the firm and outside the firm with the key suppliers and customers, i.e. internal and external environmental collaboration. Integrating environmental thinking into supply chain management has received increasing interest in recent years. The relational view and the natural resource-based-view together suggest that environmental capabilities can be built jointly with supply chain partners and used to gain sustained competitive advantage. Several studies have been undertaken to analyse the connection between environmental activities and firm performance but most studies have taken only economic performance into account. This study pays attention also to two other dimensions of firm performance, intra-firm supply chain performance and environmental performance, and aims at presenting the linkages between them and environmental collaboration. This thesis creates a research framework for the connections between environmental collaboration and firm performance and suggests approaches to analyse these. In order to find out the key concepts and their relationship, an extensive literature review is conducted. The research framework proposes a positive connection between internal and external environmental collaboration and all three dimensions of firm performance. In addition, environmental performance and intra-firm supply chain performance are expected to contribute positively to economic performance. Hence, firms are suggested to benefit from environmental collaboration both within the firm and outside the firm. Empirical testing of the developed research framework is out of the scope of this study. However, this thesis proposes using a mixed methods research approach, including survey research and multiple case studies. Finland State of Logistics 2012 survey commissioned by the Finnish Ministry of Transport and Communications and conducted by Turku School of Economics is used as an example of data for the quantitative phase. The applicability of these two methods is discussed at a general level and with regard to analysing the research framework developed in the thesis. Future research will aim at the development of the research framework and the methods in order to confirm the connection between environmental collaboration and firm performance.

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Papper kan anses vara ett av de mest använda materialen i det dagliga livet. Tidskrifter, tidningar, böcker och diverse förpackningar är några exempel på pappersbaserade produkter. Papperets egenskaper måste anpassas till användningsändamålet. En tidskrift kräver t.ex. hög ljushet, opacitet och en slät yta hos papperet, medan dessa egenskaper är mindre viktiga för en dagstidning. Allt tryckpapper behöver vissa mekaniska egenskaper för att tåla vidarebearbetning såsom kalandrering, tryckning och vikning. Man kan bestryka papper för att förbättra dess optiska egenskaper och tryckbarhetsegenskaper. Vid bestrykning appliceras en dispersion av mineralpigment och polymerbindemedel som ett tunt lager på papperets yta. Bestrykningsskiktet kan ses som ett komplext, poröst kompositmaterial som även bidrar till papperets mekaniska egenskaper och dess processerbarhet i diverse konverteringsoperationer. Kravet på framställning av förmånligt papper med tillräckliga styrkeegenskaper ställer allt högre krav på optimeringen av pappersbestrykningsskiktets egenskaper och produktionskostnader. Målet med detta arbete var att förstå sambandet mellan pigmentbestrykningsskiktets mikrostruktur och dess makroskopiska, mekaniska egenskaper. Resultaten visar att adhesionen i gränsytan mellan pigment och bindemedel är kritisk för bestrykningsskiktets förmåga att bära mekanisk belastning. Polära vätskor är vanliga i tryckfärger och kan, eftersom de påverkar syra/bas-interaktionerna mellan pigment och latexbindemedel, försvaga denna adhesion. Resultaten tyder på att ytstyrkan hos bestruket papper kan höjas genom användning av bifunktionella dispergeringsmedel för mineralpigment. Detta medför inbesparingar i pappersproduktionen eftersom mängden bindemedel, den dyraste komponenten i bestrykningsskiktet, kan minskas.

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Captive penguins are prone to pododermatitis (bumblefoot) lesions due to sedentary habits, changes in normal activity patterns, prolonged time on hard and abrasive surfaces, and less time swimming in the water. Environmental enrichment allows the use of creative and ingenious techniques that aim to keep the captive animals occupied by increasing the range and the diversity of behavioral opportunities always respecting the ethological needs of the species. The main goal of this work was to use environmental enrichment techniques to reduce pododermatitis in a group of captive penguins. Five captive Magellanic penguins (Spheniscus magellanicus) that were showing bumblefoot lesions were followed during this project. To monitor the lesions, all animals were physically restraint 3 times a week over a period of 12 weeks. Environmental enrichment was introduced daily in the water with the goal of enhancing their time in the water for one extra hour daily. The results demonstrate that in a twelve weeks period, four animals showed significant reduction of the lesions in both feet and in two animals the lesions were completely healed. With these results we can conclude that aquatic environmental enrichment allowed this group of penguins to spend more time in the water, favoring the reduction of the bumblefoot lesions.

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The purpose of this research was to evaluate the effects of evaporative cooling in freestall on mastitis occurrence, milk production, and composition, as well as cortisol, T3 (triiodothyronine), and T4 (thyroxin) levels in lactating dairy cows. Twenty-eight multiparous cows averaging 70 ± 10 day postpartum were used in four treatments from January to March 2003. The treatments were: Day (cooling from 7:00 a.m. to 7:00 p.m.); Night (cooling from 7:00 p.m. to 7:00 a.m.); 24-hour (cooling 24-hour); and Control (no cooling). Wired cup test was used for clinical mastitis diagnosis, and the California Mastitis Test (CMT) was used to identify subclinical mastitis. Blood and milk samples were taken weekly for microbiological and hormonal analyses. The cortisol levels were higher than normal values in all treatment groups, suggesting stress conditions, but T3 and T4 levels remained normal in all groups. The occurrence of subclinical mastitis was lower in Day and Night groups than in Control and 24-hour groups. Regarding the microbiological analyses, in all groups the isolation of Corynebacterium sp. from milk samples increased while negative coagulase staphylococci (CNS) declined as etiological agents of subclinical mastitis. However, in Day and 24-hour groups, coagulase positive staphylococci (CPS) increased mainly Staphylococcus aureus (49.8% and 47.7% respectively). The Night group showed a decrease in subclinical mastitis occurrences. Our data indicate that all animals subjected to treatments presented high levels of cortisol, indicating a stress condition. The Night treatment presented a reduction in microbial isolation, suggesting a reduced susceptibility to mastitis.

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Large amplitude bus bar aeolian vibration may lead to post insulator damage. Different damping applications are used to decrease the risk of large amplitude aeolian vibration. In this paper the post insulator load caused by the bus bar aeolian vibration and the effect of damping methods are evaluated. The effects of three types of bus bar connectors and three types of primary structures are studied. Two actual damping devices, damping cable and their combinations are studied. The post insulator loads are studied with strain gage based custom made force sensors installed on the both ends of the post insulator and with the displacement sensor installed on the midpoint of the bus bar. The post insulator loads are calculated from the strain values and the damping properties are determined from the displacement history. The bus bar is deflected with a hanging weight. The weight is released and the bus bar is left to free damped vibration. Both actual bus bar vibration dampers RIBE and SBI were very effective against the aeolian vibration. Combining vibration damper with damping cable will increase the damping ratio but it may be unnecessary considering the extra effort. Bus bar connector type or primary structure have no effect on the vertical load. The bending moment at the post insulator with double sided bus bar connector is significantly higher than at the post insulator with single sided bus bar connector. No reliable conclusions about bus bar connector type effect can be done, but the roller bearing type or central bearing type connector may reduce the bending moment. The RHS steel frame as primary structure may increase the bending moment peak values since it is the least rigid primary structure type and it may start to vibrate as a response to the awakening force of the vibrating bus bar.

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This paper investigates defect detection methodologies for rolling element bearings through vibration analysis. Specifically, the utility of a new signal processing scheme combining the High Frequency Resonance Technique (HFRT) and Adaptive Line Enhancer (ALE) is investigated. The accelerometer is used to acquire data for this analysis, and experimental results have been obtained for outer race defects. Results show the potential effectiveness of the signal processing technique to determine both the severity and location of a defect. The HFRT utilizes the fact that much of the energy resulting from a defect impact manifests itself in the higher resonant frequencies of a system. Demodulation of these frequency bands through use of the envelope technique is then employed to gain further insight into the nature of the defect while further increasing the signal to noise ratio. If periodic, the defect frequency is then present in the spectra of the enveloped signal. The ALE is used to enhance the envelope spectrum by reducing the broadband noise. It provides an enhanced envelope spectrum with clear peaks at the harmonics of a characteristic defect frequency. It is implemented by using a delayed version of the signal and the signal itself to decorrelate the wideband noise. This noise is then rejected by the adaptive filter that is based upon the periodic information in the signal. Results have been obtained for outer race defects. They show the effectiveness of the methodology to determine both the severity and location of a defect. In two instances, a linear relationship between signal characteristics and defect size is indicated.

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This paper examines two passive techniques for vibration reduction in mechanical systems: the first one is based on dynamic vibration absorbers (DVAs) and the second uses resonant circuit shunted (RCS) piezoceramics. Genetic algorithms are used to determine the optimal design parameters with respect to performance indexes, which are associated with the dynamical behavior of the system over selected frequency bands. The calculation of the frequency response functions (FRFs) of the composite structure (primary system + DVAs) is performed through a substructure coupling technique. A modal technique is used to determine the frequency response function of the structure containing shunted piezoceramics which are bonded to the primary structure. The use of both techniques simultaneously on the same structure is investigated. The methodology developed is illustrated by numerical applications in which the primary structure is represented by simple Euler-Bernoulli beams. However, the design aspects of vibration control devices presented in this paper can be extended to more complex structures.

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The aim of the present work is to study the noise and vibration damping capacity of ferromagnetic Fe-16%Cr base alloys (before and after heat treatment) with different Al and Mo contents. The noise damping was evaluated by the level of sound emission after an impact. The vibration damping was studied using a cantilever device. In addition to these tests, the magnetic structure of the materials was also investigated by Kerr effect. It was verified that the materials can decrease noise level in the frequency range of human earring. The vibration damping is influenced by heat treatment and chemical composition of the alloy. The improvement of vibration damping after heat treatment is ascribed to the decrease of internal stresses in materials and changes in magnetic domain structures.

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This contribution discusses the nonlinear dynamics of a pin-ended elasto-plastic beam with both kinematic and isotropic hardening. An iterative numerical procedure based on the operator split technique is developed in order to deal with the nonlinearities in the equations of motion. Free and forced responses for harmonic sinusoidal and square wave excitations are investigated. Numerical simulations present many interesting behaviors such as jump phenomena, sensitivity to initial conditions, chaos and transient chaos. These results indicate that there are practical problems in predicting the response of the beam even when periodic steady state response is expected.