835 resultados para Improved equipment


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Background and purpose: In planning to meet evidence based needs for radiotherapy, guidelines for the provision of capital and human resources are central if access, quality and safety are not to be compromised. A component of the ESTRO-HERO (Health Economics in Radiation Oncology) project is to document the current availability and content of guidelines for radiotherapy in Europe. Materials and methods: An 84 part questionnaire was distributed to the European countries through their national scientific and professional radiotherapy societies with 30 items relating to the availability of guidelines for equipment and staffing and selected operational issues. Twenty-nine countries provided full or partial evaluable responses. Results: The availability of guidelines across Europe is far from uniform. The metrics used for capital and human resources are variable. There seem to have been no major changes in the availability or specifics of guidelines over the ten-year period since the QUARTS study with the exception of the recent expansion of RTT staffing models. Where comparison is possible it appears that staffing for radiation oncologists, medical physicists and particularly RTTs tend to exceed guidelines suggesting developments in clinical radiotherapy are moving faster than guideline updating. Conclusion: The efficient provision of safe, high quality radiotherapy services would benefit from the availability of well-structured guidelines for capital and human resources, based on agreed upon metrics, which could be linked to detailed estimates of need

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Background: Documenting the distribution of radiotherapy departments and the availability of radiotherapy equipment in the European countries is an important part of HERO the ESTRO Health Economics in Radiation Oncology project. HERO has the overall aim to develop a knowledge base of the provision of radiotherapy in Europe and build a model for health economic evaluation of radiation treatments at the European level. The aim of the current report is to describe the distribution of radiotherapy equipment in European countries. Methods: An 84-item questionnaire was sent out to European countries, principally through their national societies. The current report includes a detailed analysis of radiotherapy departments and equipment (questionnaire items 2629), analyzed in relation to the annual number of treatment courses and the socio-economic status of the countries. The analysis is based on validated responses from 28 of the 40 European countries defined by the European Cancer Observatory (ECO). Results: A large variation between countries was found for most parameters studied. There were 2192 linear accelerators, 96 dedicated stereotactic machines, and 77 cobalt machines reported in the 27 countries where this information was available. A total of 12 countries had at least one cobalt machine in use. There was a median of 0.5 simulator per MV unit (range 0.31.5) and 1.4 (range 0.44.4) simulators per department. Of the 874 simulators, a total of 654 (75%) were capable of 3D imaging (CT-scanner or CBCToption). The number of MV machines (cobalt, linear accelerators, and dedicated stereotactic machines) per million inhabitants ranged from 1.4 to 9.5 (median 5.3) and the average number of MV machines per department from 0.9 to 8.2 (median 2.6). The average number of treatment courses per year per MV machine varied from 262 to 1061 (median 419). While 69% of MV units were capable of IMRT only 49% were equipped for image guidance (IGRT). There was a clear relation between socio-economic status, as measured by GNI per capita, and availability of radiotherapy equipment in the countries. In many low income countries in Southern and Central-Eastern Europe there was very limited access to radiotherapy and especially to equipment for IMRT or IGRT. Conclusions: The European average number of MV machines per million inhabitants and per department is now better in line with QUARTS recommendations from 2005, but the survey also showed a significant heterogeneity in the access to modern radiotherapy equipment in Europe. High income countries especially in Northern-Western Europe are well-served with radiotherapy resources, other countries are facing important shortages of both equipment in general and especially machines capable of delivering high precision conformal treatments (IMRT, IGRT)

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Power transformer is the most expensive equipment on a substation. It is always necessary to get needed benefit with the lowest expenses. Producing of power transformers with reduced insulation strength is one of the possible ways to reduce expenses. Exploitation of such transformers was begun in the end of 70-th in the last century. Protection from overvoltages was done with valve-type magnetic combined surge arresters with increased blanking voltage during switching overvoltages. Nowadays there is the necessity of replacement of those devices. That’s why modernized nonlinear surge arrester was invented. This master’s thesis is focused on the use research of that modernized device in comparison with usual nonlinear surge arresters. The goal is to show the lightning overvoltages level using different types of nonlinear surge arresters and then calculations of the lightning protection reliability.

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The objective of this study is to develop an improved support unit cost allocation system for a medium-sized technology company, and to examine which options for overhead cost accounting exist. The study begins with presenting the terminology and methods associated with overhead cost accounting and responsibility accounting. Also the most common challenges and resulting benefits of overhead cost allocation system development are brought up. As one research method two case studies were conducted for benchmarking purposes. These external cases are compared with the principal company’s cost allocation system and reflected against the theoretical background. In the empirical section interviews were used as the primary source of information alongside self studying principal company’s old cost allocation method. Interviews revealed the main weaknesses of the old system and proposals for a new one, which were utilized in setting targets for developing the new system. As a result of the development process an improved support unit cost allocation system was realized for year 2009. The new system is able to handle support unit costs in more detail enhancing the transparency and fairness of resulting cost allocations. Parts of support unit costs are now seen as business units’ own costs rather than group-level overhead. Also recommendations for further development are made after analyzing how well the targets were reached.

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Water stress is a defining characteristic of Mediterranean ecosystems, and is likely to become more severe in the coming decades. Simulation models are key tools for making predictions, but our current understanding of how soil moisture controls ecosystem functioning is not sufficient to adequately constrain parameterisations. Canopy-scale flux data from four forest ecosystems with Mediterranean-type climates were used in order to analyse the physiological controls on carbon and water flues through the year. Significant non-stomatal limitations on photosynthesis were detected, along with lesser changes in the conductance-assimilation relationship. New model parameterisations were derived and implemented in two contrasting modelling approaches. The effectiveness of two models, one a dynamic global vegetation model ('ORCHIDEE'), and the other a forest growth model particularly developed for Mediterranean simulations ('GOTILWA+'), was assessed and modelled canopy responses to seasonal changes in soil moisture were analysed in comparison with in situ flux measurements. In contrast to commonly held assumptions, we find that changing the ratio of conductance to assimilation under natural, seasonally-developing, soil moisture stress is not sufficient to reproduce forest canopy CO2 and water fluxes. However, accurate predictions of both CO2 and water fluxes under all soil moisture levels encountered in the field are obtained if photosynthetic capacity is assumed to vary with soil moisture. This new parameterisation has important consequences for simulated responses of carbon and water fluxes to seasonal soil moisture stress, and should greatly improve our ability to anticipate future impacts of climate changes on the functioning of ecosystems in Mediterranean-type climates.

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The thesis examines System Integration and original equipment manufacturer (OEM) channel in the St. Petersburg drives market. The aim of the study was to increase understanding the relationship between OEM and SI and producers, problems and ongoing trends. The collected data was analyzed in order to find out which features of a power electronic drive product exercise a significant influence for the Russian companies decision. An essential part of this study was interviews as primary information sources, organized with SI and OEM companies which represented the basic SPb industry segments. The wholesalers and end users are left out from the analysis. The collected data was analyzed in order to find out which features of a power electronic drive product exercise a significant influence for the Russian companies decision.

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The amount of water available is usually restricted, which leads to a situation where a complete understanding of the process, including water circulations and the influence of water components, is essential. The main aim of this thesis was to clarify the possibilities for the efficient use of residual peroxide by means of water circulation rearrangements. Rearranging water circulations and the reduction of water usage may cause new problems, such as metal induced peroxide decomposition that needs to be addressed. This thesis introduces theoretical methods of water circulations to combine two variables; effective utilization of residual peroxide and avoiding manganese in the alkaline peroxide bleaching stage. Results are mainly based on laboratory and mill site experiments concerning the utilization of residual peroxide. A simulation model (BALAS) was used to evaluate the manganese contents and residual peroxide doses. It was shown that with optimum recirculation of residual peroxide the brightness can be improved or chemical costs can be decreased. From the scientific perspective, it was also very important to discover that recycled peroxide was more effective pre-bleaching agent compared to fresh peroxide. This can be due to the organic acids i.e. per acetic acid in wash press filtrate that have been formed in alkaline bleaching stage. Even short retention time was adequate and the activation of residual peroxide using sodium hydroxide was not necessary. There are several possibilities for using residual peroxide in practice regarding bleaching. A typical modern mechanical pulping process line consist of defibering, screening, a disc filter, a bleach press, high consistency (HC) peroxide bleaching and a wash press. Furthermore there usually is not a particular medium consistency (MC) pre-bleaching stage that includes additional thickening equipment. The most advisable way to utilize residual peroxide in this kind of process is to recycle the wash press filtrate to the dilution of disc filter pulp (low MC pre-bleaching stage). An arrangement such as this would be beneficial in terms of the reduced convection of manganese to the alkaline bleaching stage. Manganese originates from wood material and will be removed to the water phase already in the early stages of the process. Recycling residual peroxide prior to the disc filter is not recommended because of low consistencies. Regarding water circulations, the novel point of view is that, it would be beneficial to divide water circulations into two sections and the critical location for the division is the disc filter. Both of these two sections have their own priority. Section one before the disc filter: manganese removal. Section two after the disc filter: brightening of pulp. This division can be carried out if the disc filter pulp is diluted only by wash press filtrate before the MC storage tower. The situation is even better if there is an additional press after the disc filter, which will improve the consistency of the pulp. This has a significant effect on the peroxide concentration in the MC pre-bleaching stage. In terms of manganese content, it is essential to avoid the use of disc filter filtrate in the bleach press and wash press showers. An additional cut-off press would also be beneficial for manganese removal. As a combination of higher initial brightness and lower manganese content, the typical brightness increase varies between approximately 0.5 and 1% ISO units after the alkaline peroxide bleaching stage. This improvement does not seem to be remarkable, but as it is generally known, the final brightness unit is the most expensive and difficult to achieve. The estimation of cost savings is not unambiguous. For example in GW/TMP mill case 0.6% ISO units higher final brightness gave 10% savings in the costs of bleaching chemicals. With an hypothetical 200 000 ton annual production, this means that the mill could save in the costs of bleaching chemicals more than 400 000 euros per year. In general, it can be said that there were no differences between the behavior of different types of processes (GW, PGW, TMP and BCTMP). The enhancement of recycling gave a similar response in all cases. However, we have to remember that the utilization of residual peroxide in older mills depends a great deal on the process equipment, the amount of water available and existing pipeline connections. In summary, it can be said that processes are individual and the same solutions cannot be applied to all cases.

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The present paper focuses on improving chromium (III) uptake capacity of sugarcane bagasse through its chemical modification with citric acid and/or sodium hydroxide. The chemical modifications were confirmed by infrared spectroscopy, with an evident peak observed at 1730 cm-1, attributed to carbonyl groups. Equilibrium was reached after 24 h, and the kinetics followed the pseudo-second-order model. The highest chromium (III) maximum adsorption capacity (MAC) value was found when using sugarcane bagasse modified with sodium hydroxide and citric acid (58.00 mg g-1) giving a MAC value about three times greater (20.34 mg g-1) than for raw sugarcane bagasse.

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Pfaffic acid, a marker of Hebanthe eriantha (Brazilian ginseng), was first isolated in 1983 but is not yet commercially available. This lack of availability compromises the quality control of this plant and its derivatives. This paper proposes a process for pfaffic acid isolation from roots of H. eriantha at a purity suitable for analytical purposes. The steps involved in this process included extraction, hydrolysis, fractionation and purification by preparative HPLC. This process led to isolation of pfaffic acid with a chromatographic purity of 98.5% in a 0.25% yield from dried roots of H. eriantha; this yield is more than forty times higher than that of the current method in the literature.

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A study was undertaken to examine the pathogenic diversity of Pyricularia grisea isolates retrieved from 14 upland rice (Oryza sativa) cultivars in experimental plots during a period of five years. Inoculations were performed on 32 genotypes with 85 monoconidial isolates under controlled greenhouse conditions. Based on the reaction pattern of eight international differentials, eleven pathotypes of P. grisea were identified. The predominant international races or pathotypes were IB-9 (56.4%), IB-1 (16.4%) and IB-41 (11.8%). A set of eight commercial upland rice cultivars ('Carajás', 'Confiança', 'Maravilha', 'Primavera', 'Progresso', 'Caiapó', 'IAC-47', 'IAC-201') was utilized as additional differentials for describing the virulence pattern of P. grisea. Twenty-six Brazilian pathotypes were identified on the basis of disease reaction on these differentials, in contrast to the 11 international pathotypes. The most predominant Brazilian pathotypes, BB-21 and BB-41 were represented by 28.2% and 17.6% of the isolates tested, respectively. Isolates virulent and avirulent to cultivar 'Primavera' were encountered within the pathotype IB-1. Utilizing Brazilian cultivars as differentials, the 14 isolates of the pathotype IB-1could be further classified into eight local pathotypes, BB-41, BB-13, BB-21, BB-9, BB-29, BB-61, BD-9 and BG-1. Virulence to improved rice cultivars 'Canastra', 'Confiança', 'Carisma', 'Maravilha', 'Primavera' and 'Bonança' was frequent in pathogen population. Some of the Brazilian pathotypes that showed differential reaction on commercial rice cultivars could be utilized for incorporating resistance genes in susceptible cultivars improved for grain quality, by conventional breeding methods.

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Teoreettisen populaatiosynteesin avulla voidaan mallintaa tähtijoukkojen ja galaksien fotometrisiä ominaisuuksia yhdistämällä yksittäisten tähtien tuottama säteily, joka saadaan teoreettisista tähtien kehitysmalleista. Valitsemalla sopiva massajakauma syntyville tähdille voidaan muodostaa yksinkertainen tähtipopulaatio, joka koostuu saman ikäisistä ja kemialliselta koostumukseltaan yhtenäisistä tähdistä. Monimutkaisempia tähtipopulaatioita voidaan muodostaa konvoloimalla yksinkertaisten tähtipopulaatioiden luminositeetti jonkin valitun tähtienmuodostushistorian kanssa sekä yhdistämällä näin muodostettuja populaatioita. Tässä työssä tarkastellaan asymptoottisen jättiläishaaran (AGB) tähtien uusien, tarkentuneiden evoluutiomallien vaikutusta populaatiosynteesin tuloksiin niin yksinkertaisten tähtipopulaatioiden kuin galaksien mallinnukseen soveltuvien monimutkaisempien tähtipopulaatioiden kohdalla. Työn päätarkoitus on tuottaa uudistuneisiin malleihin perustuvat populaation massa-luminositeetti -suhteen ja värin väliset relaatiot (MLC-relaatiot). MLC-relaatioita voidaan käyttää populaation massan määrittämiseen sen fotometristen ominaisuuksien (väri, luminositeetti) perusteella. Lisäksi tutkitaan tähtienvälisen pölyn vaikutusta yksinkertaisen spiraaligalaksimallin MLC-relaatioihin. Työssä käytetyt tähtien kehitysmallit perustuvat julkaisuun Marigo et al. (Astronomy & Astrophysics 482, 2008). Havaitaan, että AGB-tähtien vaikutus populaation integroituun luminositeettiin on pieni näkyvillä aallonpituuksilla, mutta merkittävä lähi-infrapuna-alueella. Vaikutus MLC-relaatioihin on vastaavasti merkittävä tarkkailtaessa luminositeettia lähi-infrapunassa sekä käytettäessä värejä, joissa yhdistetään optisia ja lähi-infrapunan kaistoja. Todetaan, että MLC-relaatioiden käyttö lähi-infrapunassa edellyttää tarkentuneen AGB-vaiheen sisällyttämistä populaatiosynteesin malleihin. Tähtienvälisen pölyn vaikutus MLC-relaatioihin todetaan riippuvan käytetystä kaistasta ja väristä, mutta vaikutuksen havaitaan olevan suurin optisen ja lähi-infrapunan väriyhdistelmillä.

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The study explores knowledge transfer between retiring employees and their successors in expert work. My aim is to ascertain whether there is knowledge development or building new knowledge related to this organisational knowledge transfer between generations; in other words, is the transfer of knowledge from experienced, retiring employees to their successors merely retention of the existing organisational knowledge by distributing it from one individual to another or does this transfer lead to building new and meaningful organisational knowledge. I call knowledge transfer between generations and the possibly related knowledge building in this study knowledge sharing between generations. The study examines the organisation and knowledge management from a knowledge-based and constructionist view. From this standpoint, I see knowledge transfer as an interactive process, and the exploration is based on how the people involved in this process understand and experience the phenomenon studied. The research method is organisational ethnography. I conducted the analysis of data using thematic analysis and the articulation method, which has not been used before in organisational knowledge studies. The primary empirical data consists of theme interviews with twelve employees involved in knowledge transfer in the organisation being studied and five follow-up theme interviews. Six of the interviewees are expert duty employees due to retire shortly, and six are their successors. All those participating in the follow-up interviews are successors of those soon to retire from their expert responsibilities. The organisation in the study is a medium-sized Finnish firm, which designs and manufactures electrical equipment and systems for the global market. The results of the study show that expert work-related knowledge transfer between generations can mean knowledge building which produces new, meaningful knowledge for the organisation. This knowledge is distributed in the organisation to all those that find it useful in increasing the efficiency and competitiveness of the whole organisation. The transfer and building of knowledge together create an act of knowledge sharing between generations where the building of knowledge presupposes transfer. Knowledge sharing proceeds between the expert and the novice through eight phases. During the phases of knowledge transfer the expert guides the novice to absorb the knowledge to be transferred. With the expert’s help the novice gradually comes to understand the knowledge and in the end he or she is capable of using it in his or her work. During the phases of knowledge building the expert helps the novice to further develop the knowledge being transferred so that it becomes new, useful knowledge for the organisation. After that the novice takes the built knowledge to use in his or her work. Based on the results of the study, knowledge sharing between generations takes place in interaction and ends when knowledge is taken to use. The results I obtained in the interviews by the articulation method show that knowledge sharing between generations is shaped by the novices’ conceptions of their own work goals, knowledge needs and duties. These are not only based on the official definition of the work, but also how the novices find their work or how they prioritise the given objectives and responsibilities. The study shows that the novices see their work primarily as maintenance or development. Those primarily involved in maintenance duties do not necessarily need knowledge defined as transferred between generations. Therefore, they do not necessarily transfer knowledge with their assigned experts, even though this can happen in favourable circumstances. They do not build knowledge because their view of their work goals and duties does not require the building of new knowledge. Those primarily involved in development duties, however, do need knowledge available from their assigned experts. Therefore, regardless of circumstances they transfer knowledge with their assigned experts and also build knowledge because their work goals and duties create a basis for building new knowledge. The literature on knowledge transfer between generations has focused on describing either the knowledge being transferred or the means by which it is transferred. Based on the results of this study, however, knowledge sharing between generations, that is, transfer and building is determined by how the novice considers his or her own knowledge needs and work practices. This is why studies on knowledge sharing between generations and its implementation should be based not only on the knowledge content and how it is shared, but also on the context of the work in which the novice interprets and shares knowledge. The existing literature has not considered the possibility that knowledge transfer between generations may mean building knowledge. The results of this study, however, show that this is possible. In knowledge building, the expert’s existing organisational knowledge is combined with the new knowledge that the novice brings to the organisation. In their interaction this combination of the expert’s “old” and the novice’s “new” knowledge becomes new, meaningful organisational knowledge. Previous studies show that knowledge development between the members of an organisation is the prerequisite for organisational renewal which in turn is essential for improved competitiveness. Against this background, knowledge building enables organisational renewal and thus enhances competitiveness. Hence, when knowledge transfer between generations is followed by knowledge building, the organisation kills two birds with one stone. In knowledge transfer the organisation retains the existing knowledge and thus maintains its competitiveness. In knowledge building the organisation developsnew knowledge and thus improves its competitiveness.

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Viilunkuivaus vaneriteollisuudessa on energiaintensiivinen prosessi, josta syntyvä hukkalämpö kannattaa ottaa talteen ja hyödyntää. Työ käsittelee erilaisten lämmöntalteenottovariaatioiden tuotteistusta ja kannattavuutta, sekä sisältää laitteiston riskianalyysin. Aiemman asiakaskohtaisen räätälöinnin sijaan, laitteiston modulaarinen tuoterakenne on otettava tuotteistuksen lähtökohdaksi. Modulaarisen tuoterakenteen ansiosta erilaisiin asiakastarpeisiin pystytään vastaamaan aiempaa tehokkaammin, kiitos erilaisten variaatioiden. Standardien ja yhtenäisten rajapintojen myötä muun muassa suunnittelua, projektinhoito ja myyntiä saadaan tehostettua. Lämmöntalteenottoratkaisuille luodaan kolme eri varustelutasoa: perus, korkea ja luksus. Näillä eri varianteilla pystytään vastamaan entistä kattavammin eri markkina-alueiden asiakastarpeisiin. Kannattavuuslaskelmat todistavat, että lämmöntalteenoton avulla saadaan merkittäviä energiasäästöjä ja eri laitteistovariaatiot maksavat itsensä erittäin nopeasti takaisin, vaikka esimerkiksi sähköenergian hinta nousisi radikaalisti. Lämmöntalteenoton voidaankin katsoa olevan aina erittäin kannattavaa. Laitteistosta on tunnistettu myös tekniset riskit, joihin on puututtava välittömästi sekä lukuisia toimenpide-ehdotuksia, joiden avulla laitteiston tuomintaa voidaan tehostaa ja muuttaa turvallisemmaksi. Riskianalyysi antaa myös suuntaviivoja tuotteistukselle sekä laitteiston huolto- ja käyttöohjeistolle.