7 resultados para Limit State Functions

em Doria (National Library of Finland DSpace Services) - National Library of Finland, Finland


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Tässä diplomityössä esitetään voimalaitoksen kanavien kannakkeiden rakennesuunnittelussa tarvittavat laskentamenetelmät. Työssä rakenteiden suunnitteluun ja mitoitukseen käytetään pääasiassa Eurokoodi 3 teräsrakenteiden suunnittelustandardin mukaista rajatilamitoitusta. Lisäksi kehitetään mitoitustyökaluja tärkeimpien kanavakannakkeiden suunnitteluun. Toteutettujen mitoitustyökalujen toiminta verifioidaan lujuusopin elementtimenetelmällä tehtävin tarkistuslaskelmin. Laskentatyökalujen analyyttisen ratkaisun verifioitiin olevan varmalla puolella kaikissa tutkituissa ilmiöissä. Työssä verifioituja menetelmiä voidaan soveltaa myös muiden vastaavien rakenteiden mitoittamiseen. Työssä luotujen laskentatyökalujen sisältämät laskentamenetelmät mahdollistavat monenlaisten rakenteiden vaatimustenmukaisen suunnittelun.

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Tässä työssä tutkittiin uumajäykistettyä sandwich-rakennetta. Tutkimuksen tavoitteena oli kehittää kuormitetulle uumajäykistetylle sandwich-elementille taipuman analyyttinen laskentamenetelmä. Sellaisen kehitykselle oli tarve, koska kyseisen tyyppiselle sandwich-rakennetyypille ei ole standardisoitua taipuman laskentamenetelmää. Uumajäykistetyn sandwich-elementin taipuma on kiinnostava, koska käyttörajatilan mukainen taipumaraja on tärkein rakennetta mitoittava tekijä. Työn soveltavassa osiossa kehitettiin uumajäykistetyn sandwich-elementin taipuman analyyttinen laskentamenetelmä. Taipuman analyyttinen laskentamenetelmä kehitettiin sandwich-palkkiteorian perusteella. Keskeisimpiä ongelmia oli uumajäykisteiden taivutus- ja leikkausjäykkyyden huomioonottaminen laskennassa. Analyyttisen laskennan tuloksia verrattiin uumajäykistetylle sandwich-elementille suoritettujen taivutuskokeiden tuloksiin sekä FE-analyysin tuloksiin. Tutkimustulosten perusteella voitiin todeta kehitetyn uumajäykistetyn sandwich-elementin taipuman analyyttisen laskentamenetelmän soveltuvan taipuman laskentaan tutkitulle uumajäykistetylle sandwich-elementille. Laskentamenetelmän luotettavuuden ja toimivuusrajojen määrittämiseksi uumajäykistetty sandwich-rakenne vaatii jatkotutkimuksia.

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The thesis studies role based access control and its suitability in the enterprise environment. The aim is to research how extensively role based access control can be implemented in the case organization and how it support organization’s business and IT functions. This study points out the enterprise’s needs for access control, factors of access control in the enterprise environment and requirements for implementation and the benefits and challenges it brings along. To find the scope how extensively role based access control can be implemented into the case organization, firstly is examined the actual state of access control. Secondly is defined a rudimentary desired state (how things should be) and thirdly completed it by using the results of the implementation of role based access control application. The study results the role model for case organization unit, and the building blocks and the framework for the organization wide implementation. Ultimate value for organization is delivered by facilitating the normal operations of the organization whilst protecting its information assets.

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The aim of this master’s thesis was to document the present state and to create a development plan for Moventas Wind’s cost accounting. The current cost accounting system was evaluated and most fundamental problems were chosen as areas of focus in development work. The development plan includes both short- and long-term development proposals for problems identified. This report presents two alternative models for product costing. Benchmarking of cost accounting practices and modern cost accounting theories were used in development of cost accounting. It was found that the current cost accounting system functions quite well and the adjustments in unit cost rate calculation have only a minor influence on costs of goods sold. An OEE-based standard cycle concept was also developed and it was found that the implementation of this new system is worthwhile in the long-term.

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Cutin and suberin are structural and protective polymers of plant surfaces. The epidermal cells of the aerial parts of plants are covered with an extracellular cuticular layer, which consists of polyester cutin, highly resistant cutan, cuticular waxes and polysaccharides which link the layer to the epidermal cells. A similar protective layer is formed by a polyaromatic-polyaliphatic biopolymer suberin, which is present particularly in the cell walls of the phellem layer of periderm of the underground parts of plants (e.g. roots and tubers) and the bark of trees. In addition, suberization is also a major factor in wound healing and wound periderm formation regardless of the plants’ tissue. Knowledge of the composition and functions of cuticular and suberin polymers is important for understanding the physiological properties for the plants and for nutritional quality when these plants are consumed as foods. The aims of the practical work were to assess the chemical composition of cuticular polymers of several northern berries and seeds and suberin of two varieties of potatoes. Cutin and suberin were studied as isolated polymers and further after depolymerization as soluble monomers and solid residues. Chemical and enzymatic depolymerization techniques were compared and a new chemical depolymerization method was developed. Gas chromatographic analysis with mass spectrometric detection (GC-MS) was used to assess the monomer compositions. Polymer investigations were conducted with solid state carbon-13 cross polarization magic angle spinning nuclear magnetic resonance spectroscopy (13C CP-MAS NMR), Fourier transform infrared spectroscopy (FTIR) and microscopic analysis. Furthermore, the development of suberin over one year of post-harvest storage was investigated and the cuticular layers from berries grown in the North and South of Finland were compared. The results show that the amounts of isolated cuticular layers and cutin monomers, as well as monomeric compositions vary greatly between the berries. The monomer composition of seeds was found to differ from the corresponding berry peel monomers. The berry cutin monomers were composed mostly of long-chain aliphatic ω-hydroxy acids, with various mid-chain functionalities (double-bonds, epoxy, hydroxy and keto groups). Substituted α,ω-diacids predominated over ω-hydroxy acids in potato suberin monomers and slight differences were found between the varieties. The newly-developed closed tube chemical method was found to be suitable for cutin and suberin analysis and preferred over the solvent-consuming and laborious reflux method. Enzymatic hydrolysis with cutinase was less effective than chemical methanolysis and showed specificity towards α,ω-diacid bonds. According to 13C CP-MAS NMR and FTIR, the depolymerization residues contained significant amounts of aromatic structures, polysaccharides and possible cutan-type aliphatic moieties. Cultivation location seems to have effect on cuticular composition. The materials studied contained significant amounts of different types of biopolymers that could be utilized for several purposes with or without further processing. The importance of the so-called waste material from industrial processes of berries and potatoes as a source of either dietary fiber or specialty chemicals should be further investigated in detail. The evident impact of cuticular and suberin polymers, among other fiber components, on human health should be investigated in clinical trials. These by-product materials may be used as value-added fiber fractions in the food industry and as raw materials for specialty chemicals such as lubricants and emulsifiers, or as building blocks for novel polymers.

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Photosynthesis, the process in which carbon dioxide is converted into sugars using the energy of sunlight, is vital for heterotrophic life on Earth. In plants, photosynthesis takes place in specific organelles called chloroplasts. During chloroplast biogenesis, light is a prerequisite for the development of functional photosynthetic structures. In addition to photosynthesis, a number of other metabolic processes such as nitrogen assimilation, the biosynthesis of fatty acids, amino acids, vitamins, and hormones are localized to plant chloroplasts. The biosynthetic pathways in chloroplasts are tightly regulated, and especially the reduction/oxidation (redox) signals play important roles in controlling many developmental and metabolic processes in chloroplasts. Thioredoxins are universal regulatory proteins that mediate redox signals in chloroplasts. They are able to modify the structure and function of their target proteins by reduction of disulfide bonds. Oxidized thioredoxins are restored via the action of thioredoxin reductases. Two thioredoxin reductase systems exist in plant chloroplasts, the NADPHdependent thioredoxin reductase C (NTRC) and ferredoxin-thioredoxin reductase (FTR). The ferredoxin-thioredoxin system that is linked to photosynthetic light reactions is involved in light-activation of chloroplast proteins. NADPH can be produced via both the photosynthetic electron transfer reactions in light, and in darkness via the pentose phosphate pathway. These different pathways of NADPH production enable the regulation of diverse metabolic pathways in chloroplasts by the NADPH-dependent thioredoxin system. In this thesis, the role of NADPH-dependent thioredoxin system in the redox-control of chloroplast development and metabolism was studied by characterization of Arabidopsis thaliana T-DNA insertion lines of NTRC gene (ntrc) and by identification of chloroplast proteins regulated by NTRC. The ntrc plants showed the strongest visible phenotypes when grown under short 8-h photoperiod. This indicates that i) chloroplast NADPH-dependent thioredoxin system is non-redundant to ferredoxinthioredoxin system and that ii) NTRC particularly controls the chloroplast processes that are easily imbalanced in daily light/dark rhythms with short day and long night. I identified four processes and the redox-regulated proteins therein that are potentially regulated by NTRC; i) chloroplast development, ii) starch biosynthesis, iii) aromatic amino acid biosynthesis and iv) detoxification of H2O2. Such regulation can be achieved directly by modulating the redox state of intramolecular or intermolecular disulfide bridges of enzymes, or by protecting enzymes from oxidation in conjunction with 2-cysteine peroxiredoxins. This thesis work also demonstrated that the enzymatic antioxidant systems in chloroplasts, ascorbate peroxidases, superoxide dismutase and NTRC-dependent 2-cysteine peroxiredoxins are tightly linked up to prevent the detrimental accumulation of reactive oxygen species in plants.

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Video games industry has recently bonded California and Finland in a new way and where the employers are recruiting they also need to be aware of the provisions and procedures related to terminations. In general, collective dismissals are on a relatively high level both in Finland and in California. In California, collective redundancies are regulated under the WARN law. The WARN obligates employers with 75 or more employees to give a 60-day notice prior to a mass lay off and some other similar events. Employers with less than 75 employees are free to administer the terminations without the WARN notice period. Generally, the California at-will presumption allows employment relationship to be terminated any day with or without reason and without notice period if conditions of collective agreements or employment contract do not limit this right. Termination cannot anyhow be in violation of the anti-discrimination law. In Finland the termination related provisions are part of the Employment Contracts Act and the Act on Co-operation within Undertakings. Collective redundancies are allowed under financial and production related grounds. Small employers with less than 20 employees follow the termination provisions of the Employment Contracts Act and are obligated to inform the employee to be terminated on the details of the termination itself and also the services of the Employment and Economic Development Office. Employers with 20 or more employees are to initiate co-operation procedure under the Act on Co-operation within Undertakings when reducing personnel. The co- operation negotiations are to inform employees on the employer’s plans and financial situation as well as to involve them in the decision making regarding the terminations. The employer’s duty to inform the employees of the services of Employment and Economic Development Office needs to be fulfilled also in terminations under the co-operation procedure. Discrimination is prohibited in Finland in terminations of employment. As an alternative for terminations, employees can for example be transferred to another position or be temporarily laid off. Employer’s duties related to search of alternatives for layoff are broader in Finland than in California. The recent development of the labor laws in Finland and in California suggests that the labor law is not static in either one of these environments but changes can be expected as the needs of the business life so require.