20 resultados para Dual-beam Survey

em Helda - Digital Repository of University of Helsinki


Relevância:

20.00% 20.00%

Publicador:

Resumo:

Tutkielma käsittelee suomalaisten televisiotekstittäjien ammatillisuutta, käännösprosessia ja digitaalisten tekstitysohjelmien vaikutuksia tekstitysprosessiin ammattitekstittäjien näkökulmasta. Suomen television digitalisoituminen on aiheuttanut mullistuksia myös tekstitysalalla kun tekstitettävä kuvamateriaali on ryhdytty toimittamaan käännöstoimistoille ja tekstittäjille digitaalisena. Teoriaosuudessa käsitellään käännös- ja tekstitystutkimusta sekä koulutusta Suomessa, ammattitaitoa ja ammatillisuutta sekä kääntämisen apukeinoja. Tekstittäminen esitellään erikoistuneena kääntämisen muotona. On kuitenkin myös huomioitava, että kääntäminen on yksi vaihe tekstitysprosessissa. Teoriaosuus päättyy suomalaisten televisiotekstittäjien arjen ja työkentän nykytilanteen käsittelyyn – tekstittäjät työskentelevät monenlaisilla työehdoilla ja laadun kriteerit saatetaan joutua arvioimaan uudelleen. Empiirisen osan alussa esitetään, että suomalaisia televisiotekstittäjiä on haastateltu yllättävän vähän, ja Jääskeläisen ajatuksiin nojaten mainitaan, että tekstittämisen alalla on vielä paljon tutkimatta – etenkin suomalaisesta tekstitysprosessista löytyy tutkittavaa. Tutkimuskohde on ammatikseen televisioon tekstityksiä tekevät kääntäjät. Suomalaiselle tekstitykseen erikoistuneelle käännöstoimistolle työskenteleville tekstittäjille lähetettiin alkutalvesta 2008 kyselylomake, jolla kartoitettiin sekä monivalintakysymyksillä että avoimilla kysymyksillä heidän ammatillisuuttaan, työmenetelmiään, käännös- ja tekstitysprosessiaan, ammattiylpeyttään ja -identiteettiään, ajanhallintaansa, sekä heidän käyttämäänsä digitaalista tekstitysohjelmaa. Tutkimuksessa kävi ilmi, että lähes kolmanneksella vastaajista on ammatistaan neutraali tai jopa negatiivinen käsitys. Näitä tekstittäjiä yhdistää se seikka, että kaikilla on alle 5 vuotta kokemusta alalta. Valtaosa vastanneista on kuitenkin ylpeitä siitä, että toimivat suomen kielen ammattilaisina. Tekstitysprosessi oli lomakkeessa jaettu esikatseluvaiheeseen, käännösvaiheeseen, ajastamisvaiheeseen ja korjauskatseluvaiheeseen. Tekstittäjät pyydettiin mm. arvioimaan tekstitysprosessinsa kokonaiskestoa. Kestoissa ilmeni suuria eroavaisuuksia, joista ainakin osa korreloi kokemuksen kanssa. Runsas puolet vastaajista on hankkinut digitaalisen tekstitysohjelmiston käyttöönsä ja osa ajastaa edelleen käännöstoimistossa muun muassa ohjelmiston kalleuden vuoksi. Digitaalisen ohjelmiston myötä tekstitysprosessiin ja työkäytänteisiin on tullut muutoksia, kun videonauhureista ja televisioista on siirrytty pelkän tietokoneen käyttöön. On mahdollista tehdä etätyötä kaukomailta käsin, kääntää ja ajastaa lomittain tai tehdä esiajastus ja kääntää sitten. Digitaalinen tekniikka on siis mahdollistanut tekstitysprosessin muuttumisen ja vaihtoehtoiset työmenetelmät, mutta kaikista menetelmistä ei välttämättä ole tekstittäjälle hyötyä. Perinteinen tekstitysprosessi (esikatselu, repliikkijakojen merkitseminen käsikirjoitukseen, kääntäminen ja repliikkien laadinta, korjaukset ja tarkastuskatselu) vaikuttaa edelleen tehokkaimmalta. Vaikka työkäytänteet eroavat toisistaan, kokonaiskäsitys on se, että digitalisoitumisen alkukangertelujen jälkeen tekstittäjien työskentely on tehostunut.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Työ käsittelee Finnish Jabal Haroun Project -tutkimusryhmän Etelä-Jordaniasta inventoimalla keräämää arkeologista aineistoa (vuosilta 1999-2005) tietutkimuksen kannalta. Työn tarkoituksena on selvittää, miksi tutkimusalueella, Aaronin vuoren ympäristössä, sijaitsee tien jäänteitä ja miten tie on maastossa muinoin kulkenut. Lisäksi työ analysoi tien varsilla havaittujen rakennusten jäännösten suhdetta tiehen ja pyrkii ajoittamaan tien käyttöajankohdan (ajankohdat). Työn alkuoletuksena on, että pääosa tienvarsirakennuksista on liitettävissä tiehen ja tien sijoittuminen tutkimusalueelle johtuu pitkälti lähistöllä sijaitsevan Petran noususta merkittäväksi, Nabatealaisten harjoittaman kaupan keskukseksi, Lähi-idässä ajanlaskun alkuun mennessä. Tien jäänteitä tarkastellaan maisema-arkeologisin perustein. Tämä tarkoittaa sitä, että analyysissä korostuvat sekä kulttuuriset että ympäristölliset vaikuttimet. Niiden välistä, aikaan sidottua, suhdetta arvioidaan menneen ihmistoiminnan selittämiseksi. Tutkimusmenetelmät ovat paikkatietojärjestelmien soveltaminen, kohdekohtainen arkeologisen aineiston ja sijainnin tutkiminen, vertailevan aineiston käyttö sekä kolmiulotteinen tarkastelu. Tie ajoitetaan tienvarsikohteiden keramiikkalöytöjen avulla sekä rakenneanalyysin perusteella. Tutkimus osoittaa tien syntyneen alueen sijainnin takia. Sijainti oli edullinen suhteessa luonnonvaroihin, asutuskeskuksiin ja luontaisiin kulkuväyliin. Tien rakentajat osasivat taidokkaasti hyödyntää alueen luonnonpiirteitä ja käyttivät erityisiä menetelmiä vaikeiden tieosuuksien turvaamiseksi luonnonvoimien tuhoilta. Suurin osa tienvarsirakenteista voidaan katsoa johtuvan suoraan tien olemassaolosta, pieni osa rakenteista palveli pääsääntöisesti muita maankäytön muotoja. Petran vaikutus tien olemassaoloon ja muotoon oli suuri, kaupungin kehitys ja kukoistus näkyvät tiehen liitettävässä arkeologisessa aineistossa. Tien aktiivinen käyttö näyttää jatkuneen myös Roomalaisaikaan ensimmäisille vuosisadoille jKr., jonka jälkeen se hitaasti hiipui.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Temporomandibular disorders (TMD) and psychosocial factors reportedly associate. The underlying factors remain partially obscure, however, and further studies are required to clarify the relationships. The aims of this study were thus to assess in a non-patient working population the prevalence of TMD and related symptoms, and to clinically diagnose and follow the natural courses of TMD over a one-year period. In addition, possible comorbidity of temporomandibular and/or neck muscle pain and perceived stress and their impact on work performance were investigated, as well as how various psychosocial aspects relate to TMD. A questionnaire was mailed to all 30- to 55-year-old employees of the Finnish Broadcasting Company Ltd. whose employment in the Helsinki area had lasted at least five years (n = 1784). Of the 1339 subjects, who returned the questionnaire, 241 were examined according to the RDC/TMD and standard neck muscle palpation methods. Clinical signs of temporomandibular and/or neck muscle pain were found in 118 subjects. One-year follow-up TMD examinations were conducted on 211 subjects. The prevalence of frequent painless TMJ-related symptoms was 10%, orofacial pain 7%, neck pain 38%, and headache 15%. TMD diagnoses were: myofascial pain (13%), disc displacements (16%), and arthralgia, osteoarthritis, osteoarthrosis (4%). Chronic myofascial pain was present in 7% and chronic disc displacement with reduction in 11% of the subjects. Symptoms were significantly associated with almost all the studied psychosocial symptoms. Reduced work performance was significantly positively associated with continuous pain, severity of pain, and health stress perception, and according to logistic regression, somatization with the probability of having chronic myofascial pain. It could be concluded based on the results of this study among a non-patient working population that TMD and related symptoms are common and associated with psychosocial factors. Moreover, myofascial pain and disc displacement with reduction are the most common diagnoses of TMD. In addition, self-reported health related stress, and continuous pain in temporomandibular and/or neck muscles are associated with reduced work performance, and somatization is significantly associated with chronic myofascial pain.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

In dentistry, basic imaging techniques such as intraoral and panoramic radiography are in most cases the only imaging techniques required for the detection of pathology. Conventional intraoral radiographs provide images with sufficient information for most dental radiographic needs. Panoramic radiography produces a single image of both jaws, giving an excellent overview of oral hard tissues. Regardless of the technique, plain radiography has only a limited capability in the evaluation of three-dimensional (3D) relationships. Technological advances in radiological imaging have moved from two-dimensional (2D) projection radiography towards digital, 3D and interactive imaging applications. This has been achieved first by the use of conventional computed tomography (CT) and more recently by cone beam CT (CBCT). CBCT is a radiographic imaging method that allows accurate 3D imaging of hard tissues. CBCT has been used for dental and maxillofacial imaging for more than ten years and its availability and use are increasing continuously. However, at present, only best practice guidelines are available for its use, and the need for evidence-based guidelines on the use of CBCT in dentistry is widely recognized. We evaluated (i) retrospectively the use of CBCT in a dental practice, (ii) the accuracy and reproducibility of pre-implant linear measurements in CBCT and multislice CT (MSCT) in a cadaver study, (iii) prospectively the clinical reliability of CBCT as a preoperative imaging method for complicated impacted lower third molars, and (iv) the tissue and effective radiation doses and image quality of dental CBCT scanners in comparison with MSCT scanners in a phantom study. Using CBCT, subjective identification of anatomy and pathology relevant in dental practice can be readily achieved, but dental restorations may cause disturbing artefacts. CBCT examination offered additional radiographic information when compared with intraoral and panoramic radiographs. In terms of the accuracy and reliability of linear measurements in the posterior mandible, CBCT is comparable to MSCT. CBCT is a reliable means of determining the location of the inferior alveolar canal and its relationship to the roots of the lower third molar. CBCT scanners provided adequate image quality for dental and maxillofacial imaging while delivering considerably smaller effective doses to the patient than MSCT. The observed variations in patient dose and image quality emphasize the importance of optimizing the imaging parameters in both CBCT and MSCT.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Boron neutron capture therapy (BNCT) is a form of chemically targeted radiotherapy that utilises the high neutron capture cross-section of boron-10 isotope to achieve a preferential dose increase in the tumour. The BNCT dosimetry poses a special challenge as the radiation dose absorbed by the irradiated tissues consists of several dose different components. Dosimetry is important as the effect of the radiation on the tissue is correlated with the radiation dose. Consistent and reliable radiation dose delivery and dosimetry are thus basic requirements for radiotherapy. The international recommendations for are not directly applicable to BNCT dosimetry. The existing dosimetry guidance for BNCT provides recommendations but also calls for investigating for complementary methods for comparison and improved accuracy. In this thesis the quality assurance and stability measurements of the neutron beam monitors used in dose delivery are presented. The beam monitors were found not to be affected by the presence of a phantom in the beam and that the effect of the reactor core power distribution was less than 1%. The weekly stability test with activation detectors has been generally reproducible within the recommended tolerance value of 2%. An established toolkit for epithermal neutron beams for determination of the dose components is presented and applied in an international dosimetric intercomparison. The measured quantities (neutron flux, fast neutron and photon dose) by the groups in the intercomparison were generally in agreement within the stated uncertainties. However, the uncertainties were large, ranging from 3-30% (1 standard deviation), emphasising the importance of dosimetric intercomparisons if clinical data is to be compared between different centers. Measurements with the Exradin type 2M ionisation chamber have been repeated in the epithermal neutron beam in the same measurement configuration over the course of 10 years. The presented results exclude severe sensitivity changes to thermal neutrons that have been reported for this type of chamber. Microdosimetry and polymer gel dosimetry as complementary methods for epithermal neutron beam dosimetry are studied. For microdosimetry the comparison of results with ionisation chambers and computer simulation showed that the photon dose measured with microdosimetry was lower than with the two other methods. The disagreement was within the uncertainties. For neutron dose the simulation and microdosimetry results agreed within 10% while the ionisation chamber technique gave 10-30% lower neutron dose rates than the two other methods. The response of the BANG-3 gel was found to be linear for both photon and epithermal neutron beam irradiation. The dose distribution normalised to dose maximum measured by MAGIC polymer gel was found to agree well with the simulated result near the dose maximum while the spatial difference between measured and simulated 30% isodose line was more than 1 cm. In both the BANG-3 and MAGIC gel studies, the interpretation of the results was complicated by the presence of high-LET radiation.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Radiation therapy (RT) plays currently significant role in curative treatments of several cancers. External beam RT is carried out mostly by using megavoltage beams of linear accelerators. Tumor eradication and normal tissue complications correlate to dose absorbed in tissues. Normally this dependence is steep and it is crucial that actual dose within patient accurately correspond to the planned dose. All factors in a RT procedure contain uncertainties requiring strict quality assurance. From hospital physicist´s point of a view, technical quality control (QC), dose calculations and methods for verification of correct treatment location are the most important subjects. Most important factor in technical QC is the verification that radiation production of an accelerator, called output, is within narrow acceptable limits. The output measurements are carried out according to a locally chosen dosimetric QC program defining measurement time interval and action levels. Dose calculation algorithms need to be configured for the accelerators by using measured beam data. The uncertainty of such data sets limits for best achievable calculation accuracy. All these dosimetric measurements require good experience, are workful, take up resources needed for treatments and are prone to several random and systematic sources of errors. Appropriate verification of treatment location is more important in intensity modulated radiation therapy (IMRT) than in conventional RT. This is due to steep dose gradients produced within or close to healthy tissues locating only a few millimetres from the targeted volume. The thesis was concentrated in investigation of the quality of dosimetric measurements, the efficacy of dosimetric QC programs, the verification of measured beam data and the effect of positional errors on the dose received by the major salivary glands in head and neck IMRT. A method was developed for the estimation of the effect of the use of different dosimetric QC programs on the overall uncertainty of dose. Data were provided to facilitate the choice of a sufficient QC program. The method takes into account local output stability and reproducibility of the dosimetric QC measurements. A method based on the model fitting of the results of the QC measurements was proposed for the estimation of both of these factors. The reduction of random measurement errors and optimization of QC procedure were also investigated. A method and suggestions were presented for these purposes. The accuracy of beam data was evaluated in Finnish RT centres. Sufficient accuracy level was estimated for the beam data. A method based on the use of reference beam data was developed for the QC of beam data. Dosimetric and geometric accuracy requirements were evaluated for head and neck IMRT when function of the major salivary glands is intended to be spared. These criteria are based on the dose response obtained for the glands. Random measurement errors could be reduced enabling lowering of action levels and prolongation of measurement time interval from 1 month to even 6 months simultaneously maintaining dose accuracy. The combined effect of the proposed methods, suggestions and criteria was found to facilitate the avoidance of maximal dose errors of up to even about 8 %. In addition, their use may make the strictest recommended overall dose accuracy level of 3 % (1SD) achievable.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Diagnostic radiology represents the largest man-made contribution to population radiation doses in Europe. To be able to keep the diagnostic benefit versus radiation risk ratio as high as possible, it is important to understand the quantitative relationship between the patient radiation dose and the various factors which affect the dose, such as the scan parameters, scan mode, and patient size. Paediatric patients have a higher probability for late radiation effects, since longer life expectancy is combined with the higher radiation sensitivity of the developing organs. The experience with particular paediatric examinations may be very limited and paediatric acquisition protocols may not be optimised. The purpose of this thesis was to enhance and compare different dosimetric protocols, to promote the establishment of the paediatric diagnostic reference levels (DRLs), and to provide new data on patient doses for optimisation purposes in computed tomography (with new applications for dental imaging) and in paediatric radiography. Large variations in radiation exposure in paediatric skull, sinus, chest, pelvic and abdominal radiography examinations were discovered in patient dose surveys. There were variations between different hospitals and examination rooms, between different sized patients, and between imaging techniques; emphasising the need for harmonisation of the examination protocols. For computed tomography, a correction coefficient, which takes individual patient size into account in patient dosimetry, was created. The presented patient size correction method can be used for both adult and paediatric purposes. Dental cone beam CT scanners provided adequate image quality for dentomaxillofacial examinations while delivering considerably smaller effective doses to patient compared to the multi slice CT. However, large dose differences between cone beam CT scanners were not explained by differences in image quality, which indicated the lack of optimisation. For paediatric radiography, a graphical method was created for setting the diagnostic reference levels in chest examinations, and the DRLs were given as a function of patient projection thickness. Paediatric DRLs were also given for sinus radiography. The detailed information about the patient data, exposure parameters and procedures provided tools for reducing the patient doses in paediatric radiography. The mean tissue doses presented for paediatric radiography enabled future risk assessments to be done. The calculated effective doses can be used for comparing different diagnostic procedures, as well as for comparing the use of similar technologies and procedures in different hospitals and countries.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Financing trade between economic agents located in different countries is affected by many types of risks, resulting from incomplete information about the debtor, the problems of enforcing international contracts, or the prevalence of political and financial crises. Trade is important for economic development and the availability of trade finance is essential, especially for developing countries. Relatively few studies treat the topic of political risk, particularly in the context of international lending. This thesis explores new ground to identify links between political risk and international debt defaults. The core hypothesis of the study is that the default probability of debt increases with increasing political risk in the country of the borrower. The thesis consists of three essays that support the hypothesis from different angles of the credit evaluation process. The first essay takes the point of view of an international lender assessing the credit risk of a public borrower. The second investigates creditworthiness assessment of companies. The obtained results are substantiated in the third essay that deals with an extensive political risk survey among finance professionals in developing countries. The financial instruments of core interest are export credit guaranteed debt initiated between the Export Credit Agency of Finland and buyers in 145 countries between 1975 and 2006. Default events of the foreign credit counterparts are conditioned on country-specific macroeconomic variables, corporate-specific accounting information as well as political risk indicators from various international sources. Essay 1 examines debt issued to government controlled institutions and conditions public default events on traditional macroeconomic fundamentals, in addition to selected political and institutional risk factors. Confirming previous research, the study finds country indebtedness and the GDP growth rate to be significant indicators of public default. Further, it is shown that public defaults respond to various political risk factors. However, the impact of the risk varies between countries at different stages of economic development. Essay 2 proceeds by investigating political risk factors as conveivable drivers of corporate default and uses traditional accounting variables together with new political risk indicators in the credit evaluation of private debtors. The study finds links between corporate default and leverage, as well as between corporate default and the general investment climate and measeures of conflict in the debtor country. Essay 3 concludes the thesis by offering survey evidence on the impact of political risk on debt default, as perceived and experienced by 103 finance professionals in 38 developing countries. Taken together, the results of the thesis suggest that various forms of political risk are associated with international debt defaults and continue to pose great concerns for both international creditors and borrowers in developing countries. The study provides new insights on the importance of variable selection in country risk analysis, and shows how political risk is actually perceived and experienced in the riskier, often lower income countries of the global economy.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The aim of the current study is to examine the influence of the channel external environment on power, and the effect of power on the distribution network structure within the People’s Republic of China. Throughout the study a dual research process was applied. The theory was constructed by elaborating the main theoretical premises of the study, the channel power theories, the political economy framework and the distribution network structure, but these marketing channel concepts were expanded with other perspectives from other disciplines. The main method applied was a survey conducted among 164 Chinese retailers, complemented by interviews, photographs, observations and census data from the field. This multi-method approach enabled not only to validate and triangulate the quantitative results, but to uncover serendipitous findings as well. The theoretical contribution of the current study to the theory of marketing channels power is the different view it takes on power. First, earlier power studies have taken the producer perspective, whereas the current study also includes a distributor perspective to the discussion. Second, many power studies have dealt with strongly dependent relationships, whereas the current study examines loosely dependent relationships. Power is dependent on unequal distribution of resources rather than based on high dependency. The benefit of this view is in realising that power resources and power strategies are separate concepts. The empirical material of the current study confirmed that at least some resources were significantly related to power strategies. The study showed that the dimension resources composed of technology, know-how and knowledge, managerial freedom and reputation was significantly related to non-coercive power. Third, the notion of different outcomes of power is a contribution of this study to the channels power theory even though not confirmed by the empirical results. Fourth, it was proposed that channel external environment other than the resources would also contribute to the channel power. These propositions were partially supported thus providing only partial contribution to the channel power theory. Finally, power was equally distributed among the different types of actors. The findings from the qualitative data suggest that different types of retailers can be classified according to the meaning the actors put into their business. Some are more business oriented, for others retailing is the only way to earn a living. The findings also suggest that in some actors both retailing and wholesaling functions emerge, and this has implications for the marketing channels structure.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The occurrence of occupational chronic solvent encephalopathy (CSE) seems to decrease, but still every year reveals new cases. To prevent CSE and early retirement of solvent-exposed workers, actions should focus on early CSE detection and diagnosis. Identifying the work tasks and solvent exposure associated with high risk for CSE is crucial. Clinical and exposure data of all the 128 cases diagnosed with CSE as an occupational disease in Finland during 1995-2007 was collected from the patient records at the Finnish Institute of Occupational Health (FIOH) in Helsinki. The data on the number of exposed workers in Finland were gathered from the Finnish Job-exposure Matrix (FINJEM) and the number of employed from the national workforce survey. We analyzed the work tasks and solvent exposure of CSE patients and the findings in brain magnetic resonance imaging (MRI), quantitative electroencephalography (QEEG), and event-related potentials (ERP). The annual number of new cases diminished from 18 to 3, and the incidence of CSE decreased from 8.6 to 1.2 / million employed per year. The highest incidence of CSE was in workers with their main exposure to aromatic hydrocarbons; during 1995-2006 the incidence decreased from 1.2 to 0.3 / 1 000 exposed workers per year. The work tasks with the highest incidence of CSE were floor layers and lacquerers, wooden surface finishers, and industrial, metal, or car painters. Among 71 CSE patients, brain MRI revealed atrophy or white matter hyperintensities or both in 38% of the cases. Atrophy which was associated with duration of exposure was most frequently located in the cerebellum and in the frontal or parietal brain areas. QEEG in a group of 47 patients revealed increased power of the theta band in the frontal brain area. In a group of 86 patients, the P300 amplitude of auditory ERP was decreased, but at individual level, all the amplitude values were classified as normal. In 11 CSE patients and 13 age-matched controls, ERP elicited by a multimodal paradigm including an auditory, a visual detection, and a recognition memory task under single and dual-task conditions corroborated the decrease of auditory P300 amplitude in CSE patients in single-task condition. In dual-task conditions, the auditory P300 component was, more often in patients than in controls, unrecognizable. Due to the paucity and non-specificity of the findings, brain MRI serves mainly for differential diagnostics in CSE. QEEG and auditory P300 are insensitive at individual level and not useful in the clinical diagnostics of CSE. A multimodal ERP paradigm may, however, provide a more sensitive method to diagnose slight cognitive disturbances such as CSE.