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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

A metalogical analysis of vagueness : an exploratory study into the geometry of logic

Hovsepian, Felix January 1992 (has links)
As early as 1958 John McCarthy stressed the importance of formulating common sense knowledge, and common sense reasoning, in a rigourous manner. Today, this is considered to be the central problem in Artificial Intelligence (AI). A strong advocate of this view is Patrick Hayes, who in 1974 argued that fuzzy logic was not a useful mechanism for representing vague terms, and suggested a better formalism could be developed using Zeeman's Tolerance Geometry. Five years later, Hayes complained about AI's emphasis on toy world's and suggested that a suitable project would be to formalise our common sense knowledge of the (everyday) physical world. A project now known as Naïve Physics (NP). In this project, Hayes discussed his attempts at describing the intuitive notion of objects touching using topological techniques, and indicated that Tolerance Geometry would be a better framework for capturing this notion. This thesis investigates Hayes' suggestion of developing Tolerance Geometry into a formal framework in which one can capture such intuitive terms as bodies touching, and characterising such vague terms as being tall. The analysis in this thesis begins with a (formal) investigation of the Sorites paradox. This puzzle is singled out because it clearly illustrates the problems raised by any formal analysis of vagueness in any language. The analyses of vagueness indicate that vague predicates possess continuous interpretations, and thence demonstarte the need for a spatial structure to be incorporated into the formalised metalanguage. This metalanguage then provides the framework for the proof that the Sorites is insoluble in a logic with a truth-set given by {0,1}, but consistent in a logic with truth-set given by {0,u,1}. Furthermore, this investigation reveals that Zadeh has confused the notions of continuity and the continuum, and therefore his theory of fuzzy sets rest on a mistaken assumption.
42

Nothing : Kant's analysis and the Hegelian critique

Gungor, Tolga January 2017 (has links)
This thesis aims to throw an illuminating light on the as yet neglected concept of nothing in Kant’s system, a concept which is taken into consideration, by Kant, in accordance with the guiding thread of the categories of the understanding. My main argument is that Kant has a fourfold division of nothing and each has a transcendental function in his system. This function is basically a limiting one; setting up negative determinations without which Kant’s system would have never been constituted as it is now. It is shown in the thesis that the concept of nothing is divided basically into four: first, nothing as ens rationis that limits and thereby protects knowledge, secondly nothing as nihil privativum that defines the boundaries of phenomenal reality, thirdly nothing as ens imaginarium that makes possible the unity of experience and finally, nothing as nihil negativum that draws the lines of logical thinking. All make, in the last resort and by being the concepts of the opposite, experience possible. The thesis consists of four chapters. The first chapter is an exposition of all four divisions of nothing, the second is the display specifically of the concepts of ens rationis and nihil negativum, and the third is of the concepts of ens imaginarium and nihil privativum. The auxiliary argument of the thesis is that while Hegel makes a strong charge of externality against and thereby severely criticizes the Kantian concept of the thing-in-itself, - the concept of which I propose to be contained under the concept of ens rationis- Kant has equally convincing arguments against such a charge. This is the topic of the fourth and final chapter which has an implicit aim of creating the image of a powerful critical Hegel but on the other hand an equally enduring and war-like Kant. Kant is presented as a philosopher who has powerful responses to institute a balance between himself and his opponent. When Kant’s differing concepts of nothing are taken into account, Hegel’s attack of externality, it is maintained, appears not to have taken into account the full measure of the resources of the Kantian position. Even when it is said that the attack is against one specific concept of the thing-in-itself alone, Kant still seems to have enough resources for toleration and defence indeed.
43

Enhancing the performance of ad hoc networking by lower layer design

Prokkola, J. (Jarmo) 25 November 2008 (has links)
Abstract The research of early ad hoc-like networks, namely multi-hop packet radio networks, was mainly concentrated on lower layers (below network layer). Interestingly, the research of modern ad hoc networks has been mainly restricted to routing protocols. This is understandable, since routing is very challenging in such dynamic networks, but the drawback is that the lower layer models used in the studies are often highly simplified, giving inaccurate or even incorrect results. In addition, modern ad hoc network solutions are usually suboptimal because lower layers, not designed especially for ad hoc networking, are used. Thus, ad hoc networking performance, in general, can be notably enhanced by considering also the design of lower layers. The simple deployment and robustness make wireless ad hoc networks attractive for several applications (e.g., military, public authority, peer-to-peer civilian, and sensor networking), but the performance of the current solutions is typically not adequate. The focus of this work is on the effects of lower layer functionalities on the performance of ad hoc networks, while also taking into account the effects of upper layers (e.g., the effect of application traffic models). A CDMA (Code Division Multiple Access) based dual channel flat ad hoc network solution, incorporating cross-layering between all three lowest layers, is proposed and analyzed. The main element of this is the Bi-Code Channel Access (BCCA) method, in which a common code channel is used for broadcast information (e.g., route discovery), while a receiver-specific code channel is used for all directed transmissions. In addition, a new MAC (Medium Access Control) solution designed for BCCA is presented. Moreover, a novel network layer spreading code distribution (NSCD) method is presented. The advantage of these methods is that they are designed especially to be used in ad hoc networks. With an extensive set of case studies, it is shown that the presented methods outperform the typically used ad hoc network solutions (based on IEEE 802.11) in different kind of scenarios, environments, modeling concepts, and with different parameters. Detailed simulations are carried out in order to analyze the effects of different features at the lower layers, finding also interesting phenomena and dependencies between different layers. It is also shown that close attention should be paid to lower layer modeling even though the overall network performance would be in focus. In addition, various interesting features and behavior models regarding ad hoc networking are brought up. / Tiivistelmä Ensimmäiset tutkimukset rakenteettomista (ad hoc) verkoista esiintyivät nimellä monihyppypakettiradioverkot, ja ne koskivat pääasiassa verkkokerroksen alapuolella olevia tietoliikennekerroksia, mutta nykyiset tutkimukset ovat kuitenkin keskittyneet pääasiassa reititysprotokolliin. Tämä on sikäli ymmärrettävää, että reititys on hyvin haasteellista tämän tyyppisissä dynaamisissa verkoissa, mutta ongelma on, että käytetyt alempien kerrosten mallit ovat usein hyvinkin yksinkertaistettuja, mikä voi johtaa epätarkkoihin tai jopa vääriin tuloksiin. Tämän lisäksi nykyiset ehdotetut rakenteettomien verkkojen ratkaisut ovat usein tehottomia, sillä käytettyjä alempien kerrosten ratkaisuja ei ole tarkoitettu tällaisiin verkkoihin. Niinpä rakenteettomien verkkojen suorituskykyä voidaan parantaa huomattavasti kiinnittämällä huomiota alempien kerrosten suunnitteluun. Verkkojen rakenteettomuus on ajatuksena houkutteleva useissa käyttökohteissa (esimerkiksi sotilasympäristössä, viranomaiskäytössä, käyttäjien välisissä suorissa yhteyksissä ja sensoriverkoissa), mutta suorituskyky ei useinkaan ole riittävällä tasolla käytännön sovelluksiin. Työssä tutkitaan pääasiassa alempien kerrosten toiminnallisuuden vaikutusta rakenteettomien verkkojen suorituskykyyn ottaen huomioon myös ylemmät kerrokset, kuten sovellustason mallit. Työssä esitellään ja analysoidaan koodijakomonikäyttöön (CDMA, Code Division Multiple Access) perustuva kaksikanavainen tasaisen rakenteettoman verkon ratkaisu, jossa hyödynnetään kaikkien kolmen alimman kerroksen välistä keskinäistä viestintää. Ratkaisun ydin on BCCA-menetelmä (Bi-Code Channel Access), jossa käytetään kahta kanavaa tiedonsiirtoon. Yksi kanava on tarkoitettu kaikille yhteiseksi kontrollikanavaksi (esimerkiksi reitinmuodostus voi käyttää tätä kanavaa), kun taas toinen kanava on käyttäjäkohtainen kanava, jota käytetään suoraan viestittämiseen kyseiselle käyttäjälle (varsinainen data yms.). Tämän lisäksi esitellään myös BCCA-menetelmää varten suunniteltu kanavakontrollimenetelmä sekä verkkotasolla toimiva hajotuskooditiedon jakamiseen tarkoitettu menetelmä. Näiden uusien menetelmien etu on se, että ne on suunniteltu nimenomaan rakenteettomiin verkkoihin. Kattavan testivalikoiman avulla osoitetaan, että esitetty uusi ratkaisu peittoaa tyypilliset IEEE 802.11 -standardiin pohjautuvat rakenteettomien verkkojen ratkaisut. Testeissä käytetään erityyppisiä verkkorakenteita, ympäristöjä, mallinnusmenetelmiä ja parametreja. Yksityiskohtaisissa simuloinneissa ajetaan eri testitapauksia ja selvitetään, miten alempien kerrosten eri menetelmät missäkin tapauksessa vaikuttavat suorituskykyyn. Alempien kerrosten mallinnuksessa on syytä olla tarkkana, sillä työssä käy ilmi, että mallinnusvirheillä voi olla suurikin vaikutus myös ylempien kerrosten suorituskykyyn. Työ myös paljastaa useita mielenkiintoisia ilmiöitä ja vuorovaikutussuhteita, jotka liittyvät tutkittujen menetelmien ja yleisesti rakenteettomien verkkojen toimintaan.
44

芒芒禹迹: 大禹傳說源流考= Vast traces, fragmented grounds: the origins and evolution of the legend of the Great Yu

陳嘉禮, 06 November 2014 (has links)
神話傳說的創造和史實的理解,是古史學研究兩種並存的趨勢。古代社會留下了很多歷史化的神話,成為後世「神話化歷史」的基礎。傳世文獻對中國上古史的描繪,是一種神話化後的歷史結構,這是中國文化中對古史神秘化、神聖化的理解。 大禹傳說,是中國早期神話。有關大禹的文獻描述往往也不合史實。20世紀疑古運動對大禹傳說的質疑,揭櫫大禹研究新一頁,加上近百年考古學長足的發展,史學家紛紛對大禹傳說真偽作出考辨。經過近百年的討論,夏朝已經得到證實,作為歷史人物的身份也逐漸得到確認。不過,前輩學者多集中討論大禹其人其事的真偽,忽略了大禹傳說的演變。為了彌補這個缺失,本文試圖全面探索大禹傳說的演變過程及其中添加或減少之元素,以重構大禹的歷史圖像,並呈現史學發展進程中有關對大禹叙述的各種變化。 本文嘗試運用多學科及跨文化視野下,以重整大禹傳說演變的歷史。文中廣泛地利用古籍、官方或民間的資料,並配合神話、傳說、民間野史、四部資料、古文字學、非物質資料等,冀望能為大禹研究提供全新的面貌,既可為中國上古史有關帝王聖賢傳說收補苴之效,亦能引導對中國史學發展的新認識。 As two parallel tendencies in historical research, the exploration of myths and investigation of historical facts have through time directed the construction of “mythologized histories.” Confirming the fondness of Chinese culture over the fabrication of myths, related written records have further allowed history to incorporate elements in mythology. One of the earliest Chinese myths, the legend of the Great Yu, is known for the many unverified written records that document his existence. Revived by the 20th century movement of Doubting Antiquity and credible archaeological findings, historians took off on a race to reconstruct the story of the Great Yu. After a hundred years of investigation and debate, the factual existence of the Xia Dynasty has received affirmation; the legend of the Great Yu, on the other hand, is slowly being confirmed as historians continue to devote much effort in verifying truth and lies. Under this context, the evolution of the Great Yu’s legend through time is often pushed out of the picture. This thesis aims to contribute to the reconstruction of the myth by analyzing such changes in hopes of coming closer to a more accurate sketch of one of the legendary rulers in early China. Adopting a multidisciplinary and trans-cultural approach, this thesis utilizes a collection of documents from myths, legends, folklore, the four categories (sibu), paleography and other non-written sources, eventually constructing a new perspective of the Great Yu that further contributes to future research in ancient history and Chinese historiography.
45

Copper(I) catalyzed borylation and cross-coupling reactions / Kupfer(I) katalysiert Borylierung und Kreuzkupplungen

Eichhorn, Antonius January 2018 (has links) (PDF)
The present thesis comprises synthesis and stoichiometric model reactions of well-defined NHC-stabilized copper(I) complexes (NHC = N-heterocyclic carbene) in order to understand their basic reactivity in borylation and cross-coupling reactions. This also includes the investigations of the reactivity of the ligands used (NHCs and CaaCs = cyclic alkyl(amino)carbenes) with the substrates, i.e. diboron(4) esters and arylboronates, which are addressed in the second part of the thesis. / Die dargelegte Arbeit gliedert sich in zwei Teile. In einem ersten wird die Synthese sowie stöchiometrische Modell-Reaktionen von definierten NHC-stabilisierten Kupfer(I)-Komplexen (NHC = N-heterocyclisches Carben) untersucht, um Einblick in das grundlegende Reaktionsverhalten in Borylierungs- und Kreuzkupplungsreaktionen zu erlangen. Der zweite Teil adressiert die Reaktivität der eingesetzten Liganden (NHCs und CaaCs = cyclische Alkyl Amino Carbene) gegenüber verwendeten sowie möglichen Substraten (Arylboronsäureester und Diboran(4)-Verbindungen).
46

Caracterização do material particulado em Cubatão / CHARACTERIZATION OF PARTICULATE MATTER IN CUBATÃO

Valarini, Simone Fernandes 05 May 2011 (has links)
Neste trabalho foi feita uma caracterização do material particulado coletado no Centro de Capacitação e Pesquisa em Meio Ambiente (CEPEMA) localizado na cidade de Cubatão, na Baixada Santista. As coletas ocorreram entre março de 2009 e novembro de 2010, utilizando amostradores de material particulado fino, grosso e inalável (Mini-Vol) e um impactador em cascata (MOUDI) para as várias frações do material particulado, durante oito campanhas experimentais. Foi realizada uma caracterização climatológica com os dados de temperatura, pressão atmosférica, umidade relativa, velocidade e direção do vento das estações da CETESB em Cubatão: Centro (10 anos), Vila Parisi (10 anos) e Vale do Mogi (4 anos). Os dados de chuva foram obtidos da Defesa Civil para a cidade de Santos. A maior parte das coletas de 2009 ocorreu em períodos em que houve precipitação, ao passo que as coletas de 2010 foram amostradas em períodos mais secos. O material particulado fino (MPF) teve concentrações médias de: 15,7 e 18,8 g m-3 em 2009 e 2010, respectivamente, quando coletado pelo MOUDI; e 15,8 e 23,6 g m-3, quando coletado pelo Mini-Vol. O material particulado grosso (MPG) teve concentrações médias de: 11,4 e 14,1 g m-3 em 2009 e 2010, respectivamente, quando coletado pelo MOUDI; e 18,9 e 13,4 g m-3, quando coletado pelo Mini-Vol. As análises de refletância mostraram que o Black Carbon está quase totalmente no MPF, chegando a 15% (20%) da massa do MPF quando coletado pelo MOUDI (Mini-Vol). Os íons dominantes são sulfato (SO42), nitrato (NO3), sódio (Na+), amônio (NH4+) e cálcio (Ca2+) e os elementos dominantes são enxofre (S), silício (Si) e ferro (Fe). As distribuições de tamanho mostram uma moda de nucleação bastante pronunciada para o S, K, Cl e P, indicando a contribuição de fontes antropogênicas e formação secundária do aerossol. As maiores concentrações de Si, Cl, Ca, Fe, Ca2+, NO3 e Na+ se encontram no MPG. Para o Cl e Na+, foram encontradas maiores concentrações nas amostras diurnas com vento do quadrante sul-sudoeste na estação do Centro, demonstrando a contribuição marinha. / This work evaluated the particulate matter (PM) collected at the Environmental Research and Training Center (CEPEMA) located in Cubatão City. Sampling was made between 2009, March and 2010, November for fine, coarse and inhalable aerosol (Mini-Vol) and for the various fractions of PM with a cascade impactor (MOUDI) during eight experimental campaigns. A climatological study was performed for temperature, pressure, relative humidity, wind speed and direction using data from CETESB stations: Centro (10 years), Vila Parisi (10 years) and Vale do Mogi (4 years). Precipitation data was obtained from the Civil Defense for the city of Santos. Most samplings made during 2009 were concomitant with rainy days, whereas 2010 samplings were made in drier periods. Fine particulate matter (FPM) had average concentrations of: 15.7 and 18.8 g m-3 in 2009 and 2010, respectively, with MOUDI and 15.8 and 23.6 g m-3, with Mini-Vol. Coarse Particulate Matter (CPM) had average concentrations of: 11.4 and 14.1 g m-3 in 2009 and 2010, respectively, with MOUDI, and 18.9 and 13.4 g m-3, with Mini-Vol. Reflectance analysis showed that the Black Carbon is almost completely in the FPM, reaching up to 15 % (20 %) of the FPM mass when sampled with MOUDI (Mini-Vol). Dominant ions are sulfate (SO42-), nitrate (NO3-), sodium (Na+), ammonium (NH4+) and calcium (Ca2+) and the dominant elements are sulfur (S), silicon (Si) and iron (Fe). The size distributions shows a very pronounced nucleation mode for the S, K, P and Cl, indicating the contribution of anthropogenic sources and secondary aerosol formation. The highest concentrations of Si, Cl, Ca, Fe, Ca2+, NO3- and Na+ are in CPM. For Cl- and Na+, major concentrations were found in samples with diurnal south-southwest wind indicating marine aerosol contribution.
47

Caracterização do material particulado em Cubatão / CHARACTERIZATION OF PARTICULATE MATTER IN CUBATÃO

Simone Fernandes Valarini 05 May 2011 (has links)
Neste trabalho foi feita uma caracterização do material particulado coletado no Centro de Capacitação e Pesquisa em Meio Ambiente (CEPEMA) localizado na cidade de Cubatão, na Baixada Santista. As coletas ocorreram entre março de 2009 e novembro de 2010, utilizando amostradores de material particulado fino, grosso e inalável (Mini-Vol) e um impactador em cascata (MOUDI) para as várias frações do material particulado, durante oito campanhas experimentais. Foi realizada uma caracterização climatológica com os dados de temperatura, pressão atmosférica, umidade relativa, velocidade e direção do vento das estações da CETESB em Cubatão: Centro (10 anos), Vila Parisi (10 anos) e Vale do Mogi (4 anos). Os dados de chuva foram obtidos da Defesa Civil para a cidade de Santos. A maior parte das coletas de 2009 ocorreu em períodos em que houve precipitação, ao passo que as coletas de 2010 foram amostradas em períodos mais secos. O material particulado fino (MPF) teve concentrações médias de: 15,7 e 18,8 g m-3 em 2009 e 2010, respectivamente, quando coletado pelo MOUDI; e 15,8 e 23,6 g m-3, quando coletado pelo Mini-Vol. O material particulado grosso (MPG) teve concentrações médias de: 11,4 e 14,1 g m-3 em 2009 e 2010, respectivamente, quando coletado pelo MOUDI; e 18,9 e 13,4 g m-3, quando coletado pelo Mini-Vol. As análises de refletância mostraram que o Black Carbon está quase totalmente no MPF, chegando a 15% (20%) da massa do MPF quando coletado pelo MOUDI (Mini-Vol). Os íons dominantes são sulfato (SO42), nitrato (NO3), sódio (Na+), amônio (NH4+) e cálcio (Ca2+) e os elementos dominantes são enxofre (S), silício (Si) e ferro (Fe). As distribuições de tamanho mostram uma moda de nucleação bastante pronunciada para o S, K, Cl e P, indicando a contribuição de fontes antropogênicas e formação secundária do aerossol. As maiores concentrações de Si, Cl, Ca, Fe, Ca2+, NO3 e Na+ se encontram no MPG. Para o Cl e Na+, foram encontradas maiores concentrações nas amostras diurnas com vento do quadrante sul-sudoeste na estação do Centro, demonstrando a contribuição marinha. / This work evaluated the particulate matter (PM) collected at the Environmental Research and Training Center (CEPEMA) located in Cubatão City. Sampling was made between 2009, March and 2010, November for fine, coarse and inhalable aerosol (Mini-Vol) and for the various fractions of PM with a cascade impactor (MOUDI) during eight experimental campaigns. A climatological study was performed for temperature, pressure, relative humidity, wind speed and direction using data from CETESB stations: Centro (10 years), Vila Parisi (10 years) and Vale do Mogi (4 years). Precipitation data was obtained from the Civil Defense for the city of Santos. Most samplings made during 2009 were concomitant with rainy days, whereas 2010 samplings were made in drier periods. Fine particulate matter (FPM) had average concentrations of: 15.7 and 18.8 g m-3 in 2009 and 2010, respectively, with MOUDI and 15.8 and 23.6 g m-3, with Mini-Vol. Coarse Particulate Matter (CPM) had average concentrations of: 11.4 and 14.1 g m-3 in 2009 and 2010, respectively, with MOUDI, and 18.9 and 13.4 g m-3, with Mini-Vol. Reflectance analysis showed that the Black Carbon is almost completely in the FPM, reaching up to 15 % (20 %) of the FPM mass when sampled with MOUDI (Mini-Vol). Dominant ions are sulfate (SO42-), nitrate (NO3-), sodium (Na+), ammonium (NH4+) and calcium (Ca2+) and the dominant elements are sulfur (S), silicon (Si) and iron (Fe). The size distributions shows a very pronounced nucleation mode for the S, K, P and Cl, indicating the contribution of anthropogenic sources and secondary aerosol formation. The highest concentrations of Si, Cl, Ca, Fe, Ca2+, NO3- and Na+ are in CPM. For Cl- and Na+, major concentrations were found in samples with diurnal south-southwest wind indicating marine aerosol contribution.
48

Caractérisation des variabilités temporelle et spatiale de la pollution en Île-de-France : De la mesure de l'exposition individuelle à la définition des sources / Characterization of the temporal and spatial variabilities of pollution in Île-de-France : From personal exposure measurements to sources definition

Languille, Baptiste 02 December 2019 (has links)
La pollution atmosphérique résulte d’un mélange complexe de composés, des gaz et des particules, dont les effets sont notoirement néfastes. Les composés organiques volatils (COV) tiennent un rôle prépondérant dans la chimie atmosphérique et sont précurseurs d’ozone et d’aérosols organiques secondaires (AOS). En Île-de-France, l’exposition à la pollution est préoccupante ; or, des incertitudes significatives sont toujours associées aux sources de polluants, ainsi qu’à leur intensité et leurs variabilités à différentes échelles de temps et très peu d’investigations ont porté sur la quantification de l’exposition individuelle. Dans ce contexte, cette thèse a cherché à mieux caractériser les variabilités temporelle et spatiale de la pollution en Île-de-France.La fiabilité discutable des capteurs portables a été dépassée par l’élaboration d’un protocole de sélection et de qualification comprenant différents tests en mesures fixes, en chambre et en mobilité. Cette nouvelle méthodologie, basée notamment sur l’utilisation d’un outil combinant différents indicateurs statistiques, a été appliquée pour retenir l’AE51, le Cairclip et le Canarin, mesurant respectivement le carbone suie (BC), le dioxyde d’azote (NO2) et les particules (PM).Ces trois capteurs ont été déployés au cours de campagnes de mesures impliquant une trentaine de volontaires. L’exposition individuelle ainsi quantifiée est plus élevée à l’automne qu’au printemps et varie de manière substantielle en fonction des différents environnements fréquentés. La proximité de la circulation routière (pour le BC et le NO2) ainsi que les activités de cuisine et la fumée de tabac (pour les PM) présentent des contributions importantes à l’exposition totale (jusqu’à 34 %, 26 % et 44 % respectivement), alors même que le temps passé dans ces environnements est faible.En plus du trafic routier, le BC est traditionnellement imputé au feu de bois. Une campagne hivernale de mesures (3,5 mois) a permis d’imputer respectivement 22 % et 47 % des COV mesurés à ces deux sources. Certains composés ont été mesurés et associés au feu de bois pour la première fois en air ambiant comme le benzènediol et le méthylbutènone. Une comparaison avec l’inventaire régional des émissions a permis d’identifier des similitudes et des différences pour proposer des améliorations. / Air pollution results from a complex mixture of compounds, gases and particulate matter, whose effects have proven to be harmful. Volatile organic compounds (VOCs) play a major role in atmospheric chemistry and are precursors of ozone and secondary organic aerosols (SOAs). In Île-de-France, exposure to pollution is a concern; however, significant uncertainties are still associated with the pollutants’ sources, as well as their intensity and variability at different time scales, and very few investigations have focused on quantifying personal exposure. In this context, this research sought to better characterize the temporal and spatial variabilities of pollution in Île-de-France.The questionable reliability of portable sensors has been addressed by the design of a selection and qualification protocol including various tests in static measurements, controlled chamber and mobility. This new methodology, based in particular on the use of a tool combining different statistical indicators, was applied to choose the AE51, Cairclip and Canarin, measuring black carbon (BC), nitrogen dioxide (NO2) and particulate matter (PM) respectively.These three sensors were deployed during measurement campaigns involving about thirty volunteers. The personal exposure thus quantified is higher in fall than in spring and varies substantially according to the different environments frequented. Proximity to road traffic (for BC and NO2) as well as cooking activities and tobacco smoke (for PM) make significant contributions to total exposure (up to 34 %, 26 % and 44 % respectively), even though the time spent in these environments is short.In addition to road traffic, BC is traditionally attributed to wood burning. A winter measurement campaign (3.5 months) attributed respectively 22 % and 47 % of the measured VOCs to these two sources. Compounds including benzenediol and methylbuteone were measured and associated with wood burning for the first time in ambient air. A comparison with the regional emissions inventory identified similarities as well as differences and suggested improvements.
49

Processamento, Caracterização Microestrutural e Mecânica da Superliga B1914 / Processing, microstructural and mechanical characterization of B1914 superalloy

Costa, Alex Matos da Silva 11 May 2009 (has links)
Neste trabalho foi avaliada a influência das condições de processamento (pouring temperature and de vazamento e condições de isolamento térmico dos moldes cerâmicos) na formação de trincas nas palhetas de turbinas policristalinas, a base da superliga B1914, produzidas por microfusão. E devido à falta de informações sobre a superliga B1914 foram levantadas informações sobre o equilíbrio de fases (THERMOCALC) e foi realizada a caracterização microestrutural e mecânica deste material desta liga no estado bruto e tratada termicamente. Todas as palhetas vazadas a 1570, 1520 e 1470 °C em moldes sem isolamento e com isolamento parcial apresentaram trincas e outros defeitos de solidificação. Já as palhetas vazadas em moldes totalmente isolados estavam livres das trincas. No entanto foram identificados aglomerados de microporos na raíz de todas as palhetas. Os resultados de simulação de fração de fases mostraram que o equilíbrio de fases da superliga B1914 é constituído majoritariamente pelas fases γ e γ\' e pelas fases minoritárias MB2, M3B2 e sigma. A caracterização microestrutural da superliga B1914 confirmou os resultados de simulação e foram identificadas as fases gama (&#947) - dendritas e os precipitados da fase gama linha (&#947\') - no interior das dendritas e na região interdendrítica. As fases M3B2 e eram os microconstituintes do eutético. Os resultados de DTA e Scheil mostraram que o processo de solidificação, da superliga B1914, ocorreu fora de equilíbrio. Nos resultados obtidos a partir dos tratamentos térmicos, ficaram evidentes as dificuldades encontradas para solubilização das placas da fase &#947\'. A integridade estrutural dos corpos-de-prova foi comprometida pela presença de defeitos de solidificação (vazios). Tanto que os valores de LR e r obtidos nos ensaios estão muito abaixo dos valores encontrados na literatura. / This study was evaluated the influence of processing conditions (temperatures of casting conditions and thermal insulation of ceramic shells) in crack formation of equiaxed B1914 turbine blades produced by investment casting. Due to lack of information about B1914 alloy was performed microstructural and mechanical characterization of this alloy material in the raw state and treated. In shells uninsulated and partly insulated, after pouring was observed casting solidification defects. However the shells in a fully insulated were not observed casting crack formation. However were identified clusters of micropores in the root of all blades. The results of simulation phase fraction showed that the balance of phases in B1914 alloy is made mostly by γ and γ\' phases and the minority phases: MB2, M3B2 and sigma. The microstructural characterization of B1914 alloy confirmed the results of simulation and were identified: gamma (γ) - dendrites and gamma prime (γ\') - inside the dendrites and interdendritic regions. The M3B2 was found in eutectic. The results of DTA and Scheil showed that the process of solidification occurred in non-equilibrium. The results obtained from the thermal treatments showed difficulties to solubilize γ\' phase. The structural integrity of samples was compromised by the presence of solidification defects (pores). Both values of LR and εr obtained in the tests are much below the values found in literature.
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Patientens behov av information och kunskap vid diabetes typ 2 : En undersökande studie om informations- och kunskapsbehovet utifrån kön, HbA1c, ålder, utbildning och duration / Patients needs for information and knowledge in type 2 diabetes : An explorative study about the needs for information and knowledge based on gender, HbA1c, age, education and duration

Nederberg, Louise, Dzibalov, Timur January 2013 (has links)
Bakgrund Diabetes typ 2 är en av de snabbast växande sjukdomarna i både Sverige och resten av världen. Vid diabetes typ 2 utgör egenvård en betydande del av behandlingen och för att klara detta behövs kunskap om sjukdomen. I sjuksköterskeyrket ingår att förse patienter med information och kunskap, bland annat genom patientundervisning. Ett flertal studier beskriver hur information och kunskap uppfattas av patienter och hur det på bästa sätt förmedlas till dem. Däremot saknas ett instrument som mäter patienternas befintliga kunskap om sjukdomen och hur de värderar information. Syfte Syftet med arbetet är att undersöka hur informations- och kunskapsbehovet vid diabetes typ 2 varierar utifrån kön, HbA1c, ålder, utbildning och duration samt identifiera de frågor där informations- och kunskapsbehovet är störst respektive lägst. Metod Arbetet grundas på en kvantitativ enkät utformad efter The Toronto Informational Needs Questionnaire-Breast Cancer och är analyserat utifrån data från 86 patienter.  Frågor ur denna enkät har behandlats i dataprogrammet Statistical Package for the Social Sciences och presenteras som deskriptiv statistik. Den teoretiska utgångspunkten för arbetet är Lazarus och Folkmans teori. Resultat Det finns ett behov av såväl mer information som kunskap hos alla de grupper som undersökts. Skillnader dem emellan kunde urskiljas. De grupper som rankat informations- och kunskapsbehovet högst är kvinnor och personer som haft diabetes typ 2 i mer än 11 år. Män rankar vikten av information lägre och anser sig i större utsträckning ha den kunskap de behöver. Frågor där information av patienterna anses vara mycket viktigt rör medicinska frågor. Kunskap kring hur sociala frågor ska hanteras värderades lägst. Diskussion Informationssökning är ett sätt att hantera den situation som uppstår när en människa drabbas av sjukdom. Hur varierar behovet mellan olika demografiska variabler som kön, ålder, utbildning, HbA1c, och duration? Hur värderar patienterna sin kunskap? Inom vilka områden finns informationsbehov och kunskapsluckor? / Background Type 2 diabetes is one of the fastest growing diseases in Sweden and the rest of the world. In type 2 diabetes self-care is an important part of the treatment and knowledge is needed to manage that. The nursing profession comprises to provide patients with information and knowledge - this is done through patient education. Several studies describe how information and knowledge is perceived by patients and the most suitable methods to pass information and knowledge on. However there is a lack of tools that measures patients existing knowledge and how they value information. Aim The aim of this study is to investigate how need for information and knowledge in diabetes type 2 varies by gender, HbA1c, age, education and duration, and to identify questions where the need for information and knowledge is the highest and the lowest. Methods The study is based on a quantitative survey designed by The Toronto Informational Needs Questionnaire - Breast Cancer and is analyzed using the data from 86 patients. Questions from this survey have been processed in a software called Statistical Package for the Social Sciences and the result is presented as descriptive statistics. The theoretical starting point for the study is the Lazarus and Folkman`s theory. Results There is a need for more information as well as knowledge in all of the groups studied. Differences between the groups were discerned and the groups that ranked the needs for information and knowledge highest were women and people who have had diabetes type2 for more than 11 years. Men rank the importance of information lower and they consider themselves to a greater extent having the necessary information. Questions where information is considered very important concern medical issues. Knowledge of how social issues would be handled; were ranked as the lowest. Discussions Searching for information is one way to handle the situation that arises when one gets ill. How requirements vary among different demographic groups, such as gender, age education, HbA1c and duration? How do patients evaluate their knowledge, and in which areas do gaps in information and knowledge exist?

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