30 resultados para Predictive values


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Antithrombotic treatment of patients with atrial fibrillation (AF) undergoing percutaneous coronary intervention (PCI) is a delicate balancing between the risk of thromboembolism and the risk of bleeding. The purpose of this dissertation was to analyze current antithrombotic treatment strategies at the periprocedural stage and report outcomes in-hospital and at 1-month follow-up, and to evaluate the effect of renal impairment and predictive values of various bleeding scores on 1-year outcome after PCI in patients with AF. The first article was based on retrospective data from 7 Finnish hospitals between 2002–2006 (n=377), while the others were based on a prospective 17-center European register (AFCAS) gathered between 2008–2010 (n=963). The main findings in patients with AF undergoing PCI were: The use of glycoprotein IIb/IIIa inhibitors during PCI was associated with a four- to five-fold increase in the risk of major bleeding (I). Uninterrupted warfarin treatment did not increase perioperative complications and seemed to decrease bleeding complications compared to heparin bridging (II). Already mild renal impairment (eGFR 60–90mL/min) was associated with a 2.3-fold risk of all-cause mortality during the 12 months following PCI (III). Major adverse cardiac events occurred in 4.5% and bleeding complications in 7.1% of patients in the AFCAS register by 1-month follow-up (IV). In a study of patients in AFCAS register, all currently used bleeding risk scores were poor predictors of bleeding complications by 1-year follow-up (V). The findings will help improve treatment strategies for this fragile patient population with a high risk of bleeding and thrombotic complications.

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Acute otitis media (AOM) is the most prevalent bacterial infection among children. Tympanometry and spectral gradient acoustic reflectometry (SG-AR) are adjunctive diagnostic tools to pneumatic otoscopy. The aim was to investigate the diagnostic accuracy and success rates of tympanometry and SG-AR performed by physicians and nurses. The study populations comprised 515 (I-II), 281 (III), and 156 (IV) outpatients (6-35 months). Physicians performed 4246 tympanometric (I) and SG-AR (II) examinations. Nurses performed 1782 (III) and 753 (IV) examinations at symptomatic and asymptomatic visits, respectively. Pneumatic otoscopy by the physician was the diagnostic standard. The accuracy of test results by physicians or nurses (I-IV) and the proportion of visits with accurate exclusive test results from both ears (III-IV) were analyzed. Type B tympanogram and SG-AR level 5 (<49˚) predicted middle ear effusion (MEE). At asymptomatic visits, type A and C1 tympanograms (peak pressure > -200 daPa) and SG-AR level 1 (>95˚) indicated healthy middle ear. Negative predictive values of type A and C1 tympanograms by nurses in excluding AOM at symptomatic and MEE at asymptomatic visits were 94% and 95%, respectively. Nurses obtained type A or C1 tympanogram from both ears at 94/459 (20%) and 81/196 (41%) of symptomatic and asymptomatic visits, respectively. SG-AR level 1 was rarely obtained from both ears. Type A and C1 tympanograms were accurate in excluding AOM at symptomatic and MEE at asymptomatic visits. However, nurses obtained these tympanograms from both ears only at one fifth of symptomatic visits and less than half of asymptomatic visits.

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Theultimate goal of any research in the mechanism/kinematic/design area may be called predictive design, ie the optimisation of mechanism proportions in the design stage without requiring extensive life and wear testing. This is an ambitious goal and can be realised through development and refinement of numerical (computational) technology in order to facilitate the design analysis and optimisation of complex mechanisms, mechanical components and systems. As a part of the systematic design methodology this thesis concentrates on kinematic synthesis (kinematic design and analysis) methods in the mechanism synthesis process. The main task of kinematic design is to find all possible solutions in the form of structural parameters to accomplish the desired requirements of motion. Main formulations of kinematic design can be broadly divided to exact synthesis and approximate synthesis formulations. The exact synthesis formulation is based in solving n linear or nonlinear equations in n variables and the solutions for the problem areget by adopting closed form classical or modern algebraic solution methods or using numerical solution methods based on the polynomial continuation or homotopy. The approximate synthesis formulations is based on minimising the approximation error by direct optimisation The main drawbacks of exact synthesis formulationare: (ia) limitations of number of design specifications and (iia) failure in handling design constraints- especially inequality constraints. The main drawbacks of approximate synthesis formulations are: (ib) it is difficult to choose a proper initial linkage and (iib) it is hard to find more than one solution. Recentformulations in solving the approximate synthesis problem adopts polynomial continuation providing several solutions, but it can not handle inequality const-raints. Based on the practical design needs the mixed exact-approximate position synthesis with two exact and an unlimited number of approximate positions has also been developed. The solutions space is presented as a ground pivot map but thepole between the exact positions cannot be selected as a ground pivot. In this thesis the exact synthesis problem of planar mechanism is solved by generating all possible solutions for the optimisation process ¿ including solutions in positive dimensional solution sets - within inequality constraints of structural parameters. Through the literature research it is first shown that the algebraic and numerical solution methods ¿ used in the research area of computational kinematics ¿ are capable of solving non-parametric algebraic systems of n equations inn variables and cannot handle the singularities associated with positive-dimensional solution sets. In this thesis the problem of positive-dimensional solutionsets is solved adopting the main principles from mathematical research area of algebraic geometry in solving parametric ( in the mathematical sense that all parameter values are considered ¿ including the degenerate cases ¿ for which the system is solvable ) algebraic systems of n equations and at least n+1 variables.Adopting the developed solution method in solving the dyadic equations in direct polynomial form in two- to three-precision-points it has been algebraically proved and numerically demonstrated that the map of the ground pivots is ambiguousand that the singularities associated with positive-dimensional solution sets can be solved. The positive-dimensional solution sets associated with the poles might contain physically meaningful solutions in the form of optimal defectfree mechanisms. Traditionally the mechanism optimisation of hydraulically driven boommechanisms is done at early state of the design process. This will result in optimal component design rather than optimal system level design. Modern mechanismoptimisation at system level demands integration of kinematic design methods with mechanical system simulation techniques. In this thesis a new kinematic design method for hydraulically driven boom mechanism is developed and integrated in mechanical system simulation techniques. The developed kinematic design method is based on the combinations of two-precision-point formulation and on optimisation ( with mathematical programming techniques or adopting optimisation methods based on probability and statistics ) of substructures using calculated criteria from the system level response of multidegree-of-freedom mechanisms. Eg. by adopting the mixed exact-approximate position synthesis in direct optimisation (using mathematical programming techniques) with two exact positions and an unlimitednumber of approximate positions the drawbacks of (ia)-(iib) has been cancelled.The design principles of the developed method are based on the design-tree -approach of the mechanical systems and the design method ¿ in principle ¿ is capable of capturing the interrelationship between kinematic and dynamic synthesis simultaneously when the developed kinematic design method is integrated with the mechanical system simulation techniques.

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Organizational values can be used as a tool for improving organization performance. The role of the leaders in building support and developing behaviours consistent with values-driven management is studied through value perceptions by the personnel in the object organization.

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The objective of this master’s thesis was to examine how corporate values come true among the white-collar employees in the case organization. It was also studied if values were perceived similarly in the different departments. Impact of organizational position and education on value orientation was tested through hypotheses based on earlier values research. There are only few value scales available for measuring organizational values. The empirical study results indicate that personnel’s perception of organizational values can be measured statistically. When defining the scale it is utmost important to link the questions and claims close to the employees’ daily working environment. In this study, Work ethic appeared as the strongest organizational value reflecting respondents’ commitment to their duties. Related to corporate values, Performance was perceived as the strongest value and Emphasis on people the weakest. Value consensus between the departments varied. According to the previous research organizational position and educational level has an impact on value perceptions. In this study, employees in superior position or with higher education perceived organizational values to come true better than subordinates or employees with lower education. Empirical data (N=229) was collected by a web-based survey questionnaire among white-collar employees in the case organization in April 2008. Statistical analyses were performed by SPSS programme.

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The purpose of this thesis is to study organizational core values and their application in practice. With the help of literature, the thesis discusses the implementation of core values and the benefits that companies can gain by doing it successfully. Also, ways in which companies can improve their values’ application to their everyday work are presented. The case company’s value implementation is evaluated through a survey research conducted on their employees. The true power of values lies in their application, and therefore, core values should be the basis for all organizational behavior, integrated into everything a company does. Applying values in practice is an ongoing process and companies should continuously work towards creating a more value-based organizational culture. If a company does this effectively, they will most likely become more successful with stakeholders as well as financially. Companies looking to turn their values into actions should start with a self-assessment. Employee surveys are effective in assessing the current level of value implementation, since employees have valuable, first-hand information regarding the situations and behaviors they face in their everyday work. After the self-assessment, things like management commitment, communication, training, and support are key success factors in value implementation.

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Bakgrund Demokratiska samhällen är sårbara och historiskt sett sällsynta. Förutsättningarna för en fungerande demokrati innefattar mer än formella institutioner eller enbart frånvaron av diktatorer och extremgrupper. För att en regim skall fungera enligt demokratiska principer behövs medborgare som stöder demokratiska värden. Därför är det av vikt att förstå de processer som får individer att känna tilltro till demokratiska värden. Trots att man kan anta att stöd för sådana värderingar utvecklas som ett resultat av social inlärning är de konkreta omständigheterna som leder till ett dylikt lärande mindre uppenbara. Den klassiska litteraturen beträffande politisk socialisation lyfte fram föräldrarna som avgörande för de ungas medborgerliga fostran, men i moderna samhällen har föräldrarna sällan som en uttalad målsättning att försöka påverka sina barns nuvarande eller framtida politiska preferenser. Den föreliggande studiens mål var att fördjupa diskursen kring politisk socialisation gen om att analysera föräldraskapets betydelse för demokratiska värderingar hos ungdomar. Metod Den föreliggande studien utgick från två slumpmässiga urval. Det ena omfattade 1341 studerande, 17 år gamla, inom andra stadiets utbildning i tre regioner i Finland (södra, syd-västra och västra) och det andra 678 studerande, 16 år gamla vid studiens inledande, från den flamländska delen av Belgien. Studien innefattade frågeformulär som besvarades under skoltid. Resultat De centrala resultaten från studien kan sammanfattas i fyra punkter. För det första kunde empatiskt tänkande konstateras vara en god förklarande variabel för ungdomars demokratiska värderingar (Artikel 1). För det andra gav studien stöd för antagandet att stödjande föräldraskap är av betydelse för utvecklingen av empati under ungdomsåren (Artikel 2). För det tredje utvärderades empati, i relation till andra betydelsefulla variabler, som förklarande variabel för demokratiska värderingar (Artikel 3). För det fjärde gav den föreliggande studien bevis för att demokratiskt föräldraskap, både direkt och indirekt, är relaterat till demokratiska värderingar hos ungdomar. Sammanfattning Sammanfattningsvis visade den föreliggande studien hur föräldraskap både direkt och indirekt kan påverka demokratiska värderingar hos ungdomar och hur dessa resultat kunde användas för demokratisk samhällsfostran.

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Tässä diplomityössä määritellään biopolttoainetta käyttävän voimalaitoksen käytönaikainen tuotannon optimointimenetelmä. Määrittelytyö liittyy MW Powerin MultiPower CHP –voimalaitoskonseptin jatkokehitysprojektiin. Erilaisten olemassa olevien optimointitapojen joukosta valitaan tarkoitukseen sopiva, laitosmalliin ja kustannusfunktioon perustuva menetelmä, jonka tulokset viedään automaatiojärjestelmään PID-säätimien asetusarvojen muodossa. Prosessin mittaustulosten avulla lasketaan laitoksen energia- ja massataseet, joiden tuloksia käytetään seuraavan optimointihetken lähtötietoina. Optimoinnin kohdefunktio on kustannusfunktio, jonka termit ovat voimalaitoksen käytöstä aiheutuvia tuottoja ja kustannuksia. Prosessia optimoidaan säätimille annetut raja-arvot huomioiden niin, että kokonaiskate maksimoituu. Kun laitokselle kertyy käyttöikää ja historiadataa, voidaan prosessin optimointia nopeuttaa hakemalla tilastollisesti historiadatasta nykytilanteen olosuhteita vastaava hetki. Kyseisen historian hetken katetta verrataan kustannusfunktion optimoinnista saatuun katteeseen. Paremman katteen antavan menetelmän laskemat asetusarvot otetaan käyttöön prosessin ohjausta varten. Mikäli kustannusfunktion laskenta eikä historiadatan perusteella tehty haku anna paranevaa katetta, niiden laskemia asetusarvoja ei oteta käyttöön. Sen sijaan optimia aletaan hakea deterministisellä optimointialgoritmilla, joka hakee nykyhetken ympäristöstä paremman katteen antavia säätimien asetusarvoja. Säätöjärjestelmä on mahdollista toteuttaa myös tulevaisuutta ennustavana. Työn käytännön osuudessa voimalaitosmalli luodaan kahden eri mallinnusohjelman avulla, joista toisella kuvataan kattilan ja toisella voimalaitosprosessin toimintaa. Mallinnuksen tuloksena saatuja prosessiarvoja hyödynnetään lähtötietoina käyttökatteen laskennassa. Kate lasketaan kustannusfunktion perusteella. Tuotoista suurimmat liittyvät sähkön ja lämmön myyntiin sekä tuotantotukeen, ja suurimmat kustannukset liittyvät investoinnin takaisinmaksuun ja polttoaineen ostoon. Kustannusfunktiolle tehdään herkkyystarkastelu, jossa seurataan katteen muutosta prosessin teknisiä arvoja muutettaessa. Tuloksia vertaillaan referenssivoimalaitoksella suoritettujen verifiointimittausten tuloksiin, ja havaitaan, että tulokset eivät ole täysin yhteneviä. Erot johtuvat sekä mallinnuksen puutteista että mittausten lyhyehköistä tarkasteluajoista. Automatisoidun optimointijärjestelmän käytännön toteutusta alustetaan määrittelemällä käyttöön otettava optimointitapa, siihen liittyvät säätöpiirit ja tarvittavat lähtötiedot. Projektia tullaan jatkamaan järjestelmän ohjelmoinnilla, testauksella ja virityksellä todellisessa voimalaitosympäristössä ja myöhemmin ennustavan säädön toteuttamisella.