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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.
121

Die heilsgeschichtliche Theologie Erich Sauers im Kontext missionarischer Verantwortung

Afflerbach, Horst 01 December 2004 (has links)
This dissertation makes an attempt to scientifically investigate Erich Sauer's theology of salvation history for the first time. Sauer grew up in a vital missionary context in the setting of the Open Brethren fellowship and the Alliance Bible School in Berlin. He studied history, philology and theology at the Humboldt University in Berlin, with the goal of promoting missions. Because of an acute eye ailment he was forced to discontinue his studies. He was invited to Wiedenest, where he found his life's work in the Bible School, which had moved in 1919. Here he worked for almost forty years as a teacher and a writer and travelling unceasingly to preach, lecture and hold biblical seminars on the topic of salvation history and missions. His theology, which is indebted to the theory of revelation history, was influenced by federal theology, theology of salvation history and the scientific, exegetic theology of German theological positivism. Sauer derives the authority of Scripture from history and develops a complex, salvation historical model, which is characterised by the classic structure of protology, soteriology and eschatology. His pre-millennial character is not dispensationally restricted, but has, rather, its own independent formation, that allows for the universal dimensions of God's completion act, without supporting a universal redemption theory. Through the high rating that he gives the position of the ecclesia in salvation history, Sauer has achieved a programmatic missions concept, which sees a missions-oriented church within every local church. With this paradigmatic theory, Sauer contributed to a revival of missions in German Brethren congregations, in conjunction with his professional colleague Schrupp. / Christian Spirituality, Church Hist and Missiology / D.Th.
122

Distribuição elementar e de radionuclídeos na produção e uso de fertilizantes fosfatados no Brasil / Elemental and radionuclides distribution in the production and use of phosphate fertilizers in Brazil

Saueia, Cátia Heloisa Rosignoli 01 September 2006 (has links)
O fertilizante é considerado um componente essencial para a agricultura, pois sua utilização aumenta e repõe os nutrientes naturais do solo, perdidos por desgaste ou erosão. No processo de obtenção dos fertilizantes fosfatados, o concentrado de rocha reage com ácido sulfúrico concentrado produzindo ácido fosfórico e sulfato de cálcio (fosfogesso), como subproduto. O ácido fosfórico é utilizado para a produção do superfosfato triplo (TSP), superfosfato simples (SSP), monoamônio fosfato (MAP) e diamônio fosfato (DAP). A rocha fosfatada usada como matéria prima apresenta em sua composição radionuclídeos das séries naturais do urânio e tório. Durante o ataque químico do concentrado de rocha, as espécies presentes na reação, estáveis e radioativas, são redistribuídas entre o ácido fosfórico (matéria prima dos fertilizantes), e o fosfogesso, de acordo com sua solubilidade e características químicas. Enquanto os fertilizantes são comercializados, o fosfogesso fica estocado em pilhas podendo impactar o meio ambiente. Com a finalidade de entender a distribuição dos elementos e dos radionuclídeos no processo industrial de produção de fertilizantes fosfatados, foram analisadas amostras de concentrado de rocha, de fertilizantes (SSP, TSP, MAP e DAP) e fosfogesso de três procedências nacionais denominadas indústrias A, B e C. A técnica utilizada para a análise elementar foi a análise por ativação com nêutrons, que permitiu analisar os elementos Ba, Co, Cr, Fe, Hf, Na, Sc, Ta, Th, U, Zn e Zr, e as terras raras, La, Ce, Nd, Sm, Eu, Tb, Yb e Lu. Os resultados obtidos permitiram concluir que em geral, as terras raras se distribuem de forma homogênea em todos os fertilizantes e no fosfogesso, exceto o Lu. Os fertilizantes SSP e TSP apresentaram concentrações de todos os elementos analisados da mesma ordem de grandeza da rocha de origem. O mesmo comportamento foi observado nos fertilizantes MAP e DAP, exceto para os elementos Co, Sc e U. Os elementos pertencentes à série radioativa natural do urânio (238U, 234U, 230Th, 226Ra e 210Pb), do tório (232Th, 228Ra e 228Th) e o K-40, foram determinados por meio da espectrometria gama e alfa. As amostras de fertilizantes MAP e DAP, que são diretamente derivadas do ácido fosfórico, apresentaram baixa concentração para o 226Ra, 228Ra e 210Pb, enquanto que para o U e Th as concentrações encontradas foram da mesma ordem de grandeza da rocha de origem. Os fertilizantes SSP e TSP, que são obtidos pela mistura de ácido fosfórico com concentrado de rocha, apresentaram concentrações mais elevadas para os radionuclídeos das séries naturais. Avaliou-se a exposição devido a sucessivas aplicações de fertilizantes e fosfogesso, calculando-se a dose interna devida à aplicação por 10, 50 e 100 anos. Os valores encontrados estão abaixo do limite de 2,4 mSv a-1, mostrando que esta prática é negligenciável. / Fertilizer is considered an essential component for agriculture, because its use increases the natural soil nutrients, which are lost slow waste or erosion. The Brazilian phosphate fertilizer is obtained by wet reaction of igneous phosphate rock with concentrated sulphuric acid, giving as final product, phosphoric acid and dihydrated calcium sulphate (phosphogypsum) as by-product. Phosphoric acid is the starting material for triple superphosphate (TSP), single superphosphate (SSP), monoammonium phosphate (MAP) and diammonium phosphate (DAP). The phosphate rock used as raw material presents in its composition, radionuclides of the U and Th natural series in. During the chemical attack of the phosphate rock, this equilibrium is disrupted and the radionuclides and the elements migrate to intermediate, final products and by-products, according to their solubility and chemical properties. While the fertilizers are commercialized, the phosphogypsum is disposed in stack piles and can cause an impact in the environment. In order to evaluate the radionuclides and the elements distribution in the industrial process of phosphate fertilizer production, samples of concentrated rock, fertilizers (SSP, TSP, MAP and DAP) and phosphogypsum from three national industries (A, B and C), were analyzed. The characterization of the elements Ba, Co, Cr, Fe, Hf, Na, Sc, Ta, Th, U, Zn and Zr, and the rare earths La, Ce, Nd, Sm, Eu, Tb, Yb and Lu, were performed by instrumental neutron activation analysis. The results obtained showed that, in general, the rare earth elements are distributed uniformly in the fertilizers and phosphogypsum, except for Lu. The elemental concentration present in the fertilizers SSP and TSP are of the same order of magnitude of the source rock. The same behavior was observed in the fertilizers MAP and DAP, except for the elements Co, Sc and U. The radionuclides of the U series (238U, 234U, 230Th, 226Ra, 210Pb) and of the Th series (232Th, 228Ra, 228Th) and 40K were determined by gamma and alpha spectrometry. The fertilizers samples, with are derived directly from phosphoric acid, MAP and DAP, presented in their composition low activity concentrations for 226Ra, 228Ra and 210Pb. For U and Th, the concentrations founded in MAP and DAP are more significant, similar to the source rock. SSP and TSP fertilizers, which are obtained by mixing phosphoric acid with different amounts of phosphate rock, presented higher concentrations of all radionuclides of the natural series. Long-term exposure due to successive fertilizer and phosphogypsum application was evaluated. Internal doses due to the application of phosphate fertilizer and phosphogypsum for 10, 50 and 100 years were below 2.4 mSv y-1, showing that the radiological impact of such practice is negligible.
123

Distribuição elementar e de radionuclídeos na produção e uso de fertilizantes fosfatados no Brasil / Elemental and radionuclides distribution in the production and use of phosphate fertilizers in Brazil

Cátia Heloisa Rosignoli Saueia 01 September 2006 (has links)
O fertilizante é considerado um componente essencial para a agricultura, pois sua utilização aumenta e repõe os nutrientes naturais do solo, perdidos por desgaste ou erosão. No processo de obtenção dos fertilizantes fosfatados, o concentrado de rocha reage com ácido sulfúrico concentrado produzindo ácido fosfórico e sulfato de cálcio (fosfogesso), como subproduto. O ácido fosfórico é utilizado para a produção do superfosfato triplo (TSP), superfosfato simples (SSP), monoamônio fosfato (MAP) e diamônio fosfato (DAP). A rocha fosfatada usada como matéria prima apresenta em sua composição radionuclídeos das séries naturais do urânio e tório. Durante o ataque químico do concentrado de rocha, as espécies presentes na reação, estáveis e radioativas, são redistribuídas entre o ácido fosfórico (matéria prima dos fertilizantes), e o fosfogesso, de acordo com sua solubilidade e características químicas. Enquanto os fertilizantes são comercializados, o fosfogesso fica estocado em pilhas podendo impactar o meio ambiente. Com a finalidade de entender a distribuição dos elementos e dos radionuclídeos no processo industrial de produção de fertilizantes fosfatados, foram analisadas amostras de concentrado de rocha, de fertilizantes (SSP, TSP, MAP e DAP) e fosfogesso de três procedências nacionais denominadas indústrias A, B e C. A técnica utilizada para a análise elementar foi a análise por ativação com nêutrons, que permitiu analisar os elementos Ba, Co, Cr, Fe, Hf, Na, Sc, Ta, Th, U, Zn e Zr, e as terras raras, La, Ce, Nd, Sm, Eu, Tb, Yb e Lu. Os resultados obtidos permitiram concluir que em geral, as terras raras se distribuem de forma homogênea em todos os fertilizantes e no fosfogesso, exceto o Lu. Os fertilizantes SSP e TSP apresentaram concentrações de todos os elementos analisados da mesma ordem de grandeza da rocha de origem. O mesmo comportamento foi observado nos fertilizantes MAP e DAP, exceto para os elementos Co, Sc e U. Os elementos pertencentes à série radioativa natural do urânio (238U, 234U, 230Th, 226Ra e 210Pb), do tório (232Th, 228Ra e 228Th) e o K-40, foram determinados por meio da espectrometria gama e alfa. As amostras de fertilizantes MAP e DAP, que são diretamente derivadas do ácido fosfórico, apresentaram baixa concentração para o 226Ra, 228Ra e 210Pb, enquanto que para o U e Th as concentrações encontradas foram da mesma ordem de grandeza da rocha de origem. Os fertilizantes SSP e TSP, que são obtidos pela mistura de ácido fosfórico com concentrado de rocha, apresentaram concentrações mais elevadas para os radionuclídeos das séries naturais. Avaliou-se a exposição devido a sucessivas aplicações de fertilizantes e fosfogesso, calculando-se a dose interna devida à aplicação por 10, 50 e 100 anos. Os valores encontrados estão abaixo do limite de 2,4 mSv a-1, mostrando que esta prática é negligenciável. / Fertilizer is considered an essential component for agriculture, because its use increases the natural soil nutrients, which are lost slow waste or erosion. The Brazilian phosphate fertilizer is obtained by wet reaction of igneous phosphate rock with concentrated sulphuric acid, giving as final product, phosphoric acid and dihydrated calcium sulphate (phosphogypsum) as by-product. Phosphoric acid is the starting material for triple superphosphate (TSP), single superphosphate (SSP), monoammonium phosphate (MAP) and diammonium phosphate (DAP). The phosphate rock used as raw material presents in its composition, radionuclides of the U and Th natural series in. During the chemical attack of the phosphate rock, this equilibrium is disrupted and the radionuclides and the elements migrate to intermediate, final products and by-products, according to their solubility and chemical properties. While the fertilizers are commercialized, the phosphogypsum is disposed in stack piles and can cause an impact in the environment. In order to evaluate the radionuclides and the elements distribution in the industrial process of phosphate fertilizer production, samples of concentrated rock, fertilizers (SSP, TSP, MAP and DAP) and phosphogypsum from three national industries (A, B and C), were analyzed. The characterization of the elements Ba, Co, Cr, Fe, Hf, Na, Sc, Ta, Th, U, Zn and Zr, and the rare earths La, Ce, Nd, Sm, Eu, Tb, Yb and Lu, were performed by instrumental neutron activation analysis. The results obtained showed that, in general, the rare earth elements are distributed uniformly in the fertilizers and phosphogypsum, except for Lu. The elemental concentration present in the fertilizers SSP and TSP are of the same order of magnitude of the source rock. The same behavior was observed in the fertilizers MAP and DAP, except for the elements Co, Sc and U. The radionuclides of the U series (238U, 234U, 230Th, 226Ra, 210Pb) and of the Th series (232Th, 228Ra, 228Th) and 40K were determined by gamma and alpha spectrometry. The fertilizers samples, with are derived directly from phosphoric acid, MAP and DAP, presented in their composition low activity concentrations for 226Ra, 228Ra and 210Pb. For U and Th, the concentrations founded in MAP and DAP are more significant, similar to the source rock. SSP and TSP fertilizers, which are obtained by mixing phosphoric acid with different amounts of phosphate rock, presented higher concentrations of all radionuclides of the natural series. Long-term exposure due to successive fertilizer and phosphogypsum application was evaluated. Internal doses due to the application of phosphate fertilizer and phosphogypsum for 10, 50 and 100 years were below 2.4 mSv y-1, showing that the radiological impact of such practice is negligible.
124

Die heilsgeschichtliche Theologie Erich Sauers im Kontext missionarischer Verantwortung

Afflerbach, Horst 01 December 2004 (has links)
This dissertation makes an attempt to scientifically investigate Erich Sauer's theology of salvation history for the first time. Sauer grew up in a vital missionary context in the setting of the Open Brethren fellowship and the Alliance Bible School in Berlin. He studied history, philology and theology at the Humboldt University in Berlin, with the goal of promoting missions. Because of an acute eye ailment he was forced to discontinue his studies. He was invited to Wiedenest, where he found his life's work in the Bible School, which had moved in 1919. Here he worked for almost forty years as a teacher and a writer and travelling unceasingly to preach, lecture and hold biblical seminars on the topic of salvation history and missions. His theology, which is indebted to the theory of revelation history, was influenced by federal theology, theology of salvation history and the scientific, exegetic theology of German theological positivism. Sauer derives the authority of Scripture from history and develops a complex, salvation historical model, which is characterised by the classic structure of protology, soteriology and eschatology. His pre-millennial character is not dispensationally restricted, but has, rather, its own independent formation, that allows for the universal dimensions of God's completion act, without supporting a universal redemption theory. Through the high rating that he gives the position of the ecclesia in salvation history, Sauer has achieved a programmatic missions concept, which sees a missions-oriented church within every local church. With this paradigmatic theory, Sauer contributed to a revival of missions in German Brethren congregations, in conjunction with his professional colleague Schrupp. / Christian Spirituality, Church Hist and Missiology / D.Th.
125

La Théurgie: des oracles chaldaïques à Proclus

Van Liefferinge, Carine January 1996 (has links)
Doctorat en philosophie et lettres / info:eu-repo/semantics/nonPublished
126

Three essays in matching mechanism design

Nesterov, Alexander 26 September 2016 (has links)
In diese Dissertation, betrachte ich das Problem der Aufteilung der unteilbaren Objekte unter Agenten, ihren Vorlieben entsprechend, und die Transfers fehlen. In Kapitel 1 studiere ich den Kompromiss zwischen Fairness und Effizienz in der Klasse der strategy-proof Aufteilungsmechanismen. Das wichtigste Ergebnis ist, dass für die strategy-proof Mechanismen folgende Effizienz- und Fairness-Kriterien nicht miteinander vereinbar sind: (1) Ex-post-Effizienz und Neidfreiheit, (2) Ordnung-Effizienz und schwache Neidfreiheit und (3) Ordnung-Effizienz und gleiche-Teilung-untere-Grenze. In Kapitel 2 ist der Fokus auf zwei Darstellungen einer Zuteilung: als probabilistische Zuordnung und als Lotterie über deterministische Zuordnungen. Um die Gestaltung der praktischen Lotterie-Mechanismen zu erleichtern schlagen wir neue Werkzeuge für den Erhalt der stochastischen Verbesserungen bei Lotterien vor. Als Anwendungen schlagen wir Lotterie Mechanismen, die die weit verbreiteten Random serial dictatorship Mechanismus verbessern, und eine Lotterie-Darstellung seiner Konkurrent, die Probabilistic serial Mechanismus, vor. In Kapitel 3 schlage ich einen neuen Mechanismus vor, der Schüler an Grundschulen zuweist: Adaptive Acceptance (AA). AA sammelt von Neumann-Morgenstern Präferenzen von Studenten über Schulen und implementiert die Zuordnung unter Verwendung eines iterativen Verfahrens, das ähnlich der vorherrschenden Immediate Acceptance (IA) ist. AA verfügt über eine starke Kombination von Anreize und Effizienzeigenschaften im Vergleich zu IA und sein Rivale, Deferred Acceptance (DA). / I consider the problem of allocating indivisible objects among agents according to their preferences when transfers are absent. In Chapter 1, I study the tradeoff between fairness and efficiency in the class of strategy-proof allocation mechanisms. The main finding is that for strategy-proof mechanisms the following efficiency and fairness criteria are mutually incompatible: (1) Ex-post efficiency and envy-freeness, (2) ordinal efficiency and weak envy-freeness and (3) ordinal efficiency and equal division lower bound. In Chapter 2, the focus is on two representations of an allocation when randomization is used: as a probabilistic assignment and as a lottery over deterministic assignments. To help facilitate the design of practical lottery mechanisms, we provide new tools for obtaining stochastic improvements in lotteries. As applications, we propose lottery mechanisms that improve upon the widely-used random serial dictatorship mechanism, and a lottery representation of its competitor, the probabilistic serial mechanism. In Chapter 3, I propose a new mechanism to assign students to primary schools: the Adaptive Acceptance rule (AA). AA collects von Neumann-Morgenstern utilities of students over schools and implements the assignment using an iterative procedure similar to the prevalent Immediate Acceptance rule (IA). AA enjoys a strong combination of incentive and efficiency properties compared to IA and its rival, the Deferred Acceptance rule (DA). In case of strict priorities, AA implements the student-optimal stable matching in dominant strategies, which dominates each equilibrium outcome of IA. In case of no priorities, AA is ex-post efficient while some equilibrium outcomes of IA are not; also, AA causes loss of ex-ante efficiency less often than DA. If, in addition, students have common ordinal preferences, AA is approximately strategy-proof and ex-ante dominates DA.
127

Dynamic semiparametric factor models

Borak, Szymon 11 July 2008 (has links)
Hochdimensionale Regressionsprobleme, die sich dynamisch entwickeln, sind in zahlreichen Bereichen der Wissenschaft anzutreffen. Die Dynamik eines solchen komplexen Systems wird typischerweise mittels der Zeitreiheneigenschaften einer geringen Anzahl von Faktoren analysiert. Diese Faktoren wiederum sind mit zeitinvarianten Funktionen von explikativen Variablen bewichtet. Diese Doktorarbeit beschäftigt sich mit einem dynamischen semiparametrischen Faktormodell, dass nichtparametrische Bewichtungsfunktionen benutzt. Zu Beginn sollen kurz die wichtigsten statistischen Methoden diskutiert werden um dann auf die Eigenschaften des verwendeten Modells einzugehen. Im Anschluss folgt die Diskussion einiger Anwendungen des Modellrahmens auf verschiedene Datensätze. Besondere Aufmerksamkeit wird auf die Dynamik der so genannten Implizierten Volatilität und das daraus resultierende Faktor-Hedging von Barrier Optionen gerichtet. / High-dimensional regression problems which reveal dynamic behavior occur frequently in many different fields of science. The dynamics of the whole complex system is typically analyzed by time propagation of few number of factors, which are loaded with time invariant functions of exploratory variables. In this thesis we consider dynamic semiparametric factor model, which assumes nonparametric loading functions. We start with a short discussion of related statistical techniques and present the properties of the model. Additionally real data applications are discussed with particular focus on implied volatility dynamics and resulting factor hedging of barrier options.
128

Essays on panel cointegration testing

Örsal, Deniz Dilan Karaman 18 March 2009 (has links)
Diese Dissertation beinhaltet vier Aufsätze, die zur Literatur der Panelkointegrationsmethodik beitragen. Der erste Aufsatz vergleicht die Eigenschaften der vier Residuen-basierten Panelkointegrationstests von Pedroni (1995, 1999) mit dem Likelihood-basierten Panelkointegrationstest von Larsson et al. (2001) in endlichen Stichproben. Die Simulationsergebnisse zeigen, dass unter den fünf untersuchten Panelkointegrationsteststatistiken die Panel-t Teststatistik von Pedroni (1995, 1999) die besten Eigenschaften in endlichen Stichproben besitzt. Der zweite Aufsatz präsentiert eine Korrektur des Beweises von Larsson et al. (2001) bezüglich der Endlichkeit der Momente der asymptotischen Trace-Statistik für den Fall, dass die Differenz zwischen der Anzahl der Variablen und der Anzahl der existierenden Kointegrationsbeziehungen eins ist. Im dritten Aufsatz wird ein neuer Likelihood-basierter Panelkointegrationstest vorgestellt, der die Existenz eines linearen Trends in dem datengenerierenden Prozess erlaubt. Dieser neue Test ist eine Erweiterung des Likelihood-Quotienten-Tests von Saikkonen und Lütkepohl (2000a) für trendbereinigte Daten auf die Paneldatenanalyse. Unter der Nullhypothese folgt die Panel-SL Teststatistik einer standardisierten Normalverteilung, wenn die Anzahl der Beobachtungen über die Zeit (T) und die Anzahl der Querschnitte (N) sequentiell gegen unendlich gehen. In einer Monte-Carlo-Studie werden die Eigenschaften des Panel-SL Tests in endlichen Stichproben untersucht. Der neue Test hat ein annehmbares empirisches Signifikanzniveau für wachsende T und N sowie eine hohe Güte in kleinen Stichproben. Der letzte Aufsatz der Dissertation analysiert die langfristige Geldnachfragefunktion in OECD Ländern mit Hilfe von Paneleinheitswurzel- und Panelkointegrationstests. Um eine mögliche Existenz einer stationären langfristigen Geldnachfragefunktion zu untersuchen, werden der Panel-SL Kointegrationstest und die Tests von Pedroni (1999) verwendet. Im Anschluss daran wird eine Paneldatenschätzung für die Geldnachfragefunktion mittels der dynamischen Kleinste-Quadrate-Methode von Mark und Sul (2003) durchgeführt. / This thesis is composed of four essays which contribute to the literature in panel cointegration methodology. The first essay compares the finite sample properties of the four residual-based panel cointegration tests of Pedroni (1995, 1999) and the likelihood-based panel cointegration test of Larsson et al. (2001). The simulation results indicate that the panel-t test statistic of Pedroni has the best finite sample properties among the five panel cointegration test statistics evaluated. The second essay presents a corrected version of the proof of Larsson et al. (2001) related to the finiteness of the moments of the asymptotic trace statistic. The proof is corrected for the case, in which the difference between the number of variables and the number of existing cointegrating relations is one. The third essay proposes a new likelihood-based panel cointegration test in the presence of a linear time trend in the data generating process. This new test is an extension of the likelihood ratio test of Saikkonen and Lütkepohl (2000) for trend-adjusted data to the panel data framework, and is called the panel SL test. Under the null hypothesis, the panel SL test statistic is standard normally distributed as the number of time periods (T) and the number of cross-sections (N) tend to infinity sequentially. By means of a Monte Carlo study the finite sample properties of the test are investigated. The new test presents reasonable size with the increase in T and N, and has high power in small samples. The last essay of the thesis analyzes the long-run money demand relation among OECD countries by panel unit root and cointegration testing techniques. The panel SL cointegration test and the tests of Pedroni (1999) are used to detect the existence of a stationary long-run money demand relation. Moreover, the money demand function is estimated with the panel dynamic ordinary least squares method of Mark and Sul (2003).
129

Entstehung von Clustern unter Berücksichtigung der Effekte regionalisierter Innovationspolitik / Emerging Clusters with Particular Emphasis on the Effects of Regionalised Innovation Policy

Anz, Michael 27 May 2010 (has links) (PDF)
Während man sich bislang auf die Gründe für die Entwicklung existierender Cluster konzentrierte, steigt das Interesse an den Prozessen, welche deren Entstehung bewirken. Diese unterscheiden sich jedoch von jenen zusammenhängen, welche ein reifes und dynamisches Cluster kennzeichnen (Bresnahan, Gambardella 2004, S. 842; Henn 2006b). Einige Beispiele haben gezeigt, dass Politik durchaus eine Rolle in der Entwicklung von Clustern spielen kann (z. B. Feldmann et al. 2005, S. 131; Dohse 2000b). Es herrscht jedoch Konsens, dass eine direkte Steuerung und Initiierung von Clustern „wishful thinking“ bleiben muss (Enright 2003, S. 104; Rosenfeld et al. 2006). Indes zeigen sich unternehmerische Akteure im Umfeld von Forschungseinrichtungen bevorteilt, wissenschaftliche Erkenntnisse in neuen Technologiefeldern zu verwerten. In jüngerer Zeit werden deshalb regionalisierte Innovationspolitiken implementiert, welche diesen Prozess unterstützen sollen. Über die Wirkungsweise und die Effekte einer solchen räumlich fokussierten Politik herrscht bislang jedoch noch Unklarheit (Raines 2002b, S. 8; Fromhold-Eisebith, Eisebith 2005, S. 1251; Kiese 03.10.2007). Diese Fragestellungen aufgreifend werden in der vorliegenden Arbeit anhand der Fallbeispiele Dresden und Leipzig die Prozesse der Clusterentstehung im Technologiebereich der Biotechnologie vor dem Hintergrund der Post-Transformationsphase Ostdeutschlands analysiert. Zudem wird die umfangreiche, regionalisierte Innovationspolitik des Freistaates Sachsen hinsichtlich ihres Beitrages bei der Clusterentstehung untersucht. Mit diesem Untersuchungsansatz wird ein Beitrag zur noch jungen Diskussion der Clusterentstehung geleistet sowie Einblick in die Wirkungsmöglichkeiten regionalisierter Innovationspolitik gegeben. Auf der Grundlage der theoretischen Diskussion zu Clustern und regionalisierter Innovationspolitik wird ein Untersuchungsmodell abgeleitet, welches sich an den multidimensionalen Analyserahmen Bathelts anlehnt (Bathelt 2002) und um die von Henn diskutierten Entstehungsdimensionen Ansiedlung, Lernen und Gründung erweitert (Henn 2006b). Schwerpunkt der empirischen Analyse ist ein Mix aus leitfadengestützten Interviews und quantitativer Analyse sozialer Netzwerke. Bei der Analyse zeigt sich, dass „klassische“ Erklärungsmuster zur Clusterentstehung teilweise auf Prozesse hinweisen, die sich so nicht feststellen lassen. Als wesentlich erweisen sich vor allem Gründungs- und Ansiedlungsprozesse. Zu ihrer Erklärung kann jedoch kaum auf einfache Standortfaktoren zurückgegriffen werden, vielmehr müssen Forschernetzwerke zur Erklärung herangezogen werden. Bei der Analyse der Effekte der regionalisierten Innovationspolitik zeigt sich, dass die Wirksamkeit maßgeblich von der Gestaltbarkeit und Anpassung der Politik an sich ändernde Governancebedingungen abhängt. Dies betrifft sowohl das regionale technologische Umfeld als auch die Region im Allgemeinen. Daneben 243 ist die Unterstützung der Erzeugung materieller Vorraussetzungen u. a. für den Erfolg von Ausgründungen, Ansiedlungen sowie von unternehmerischen Lernprozessen relevant. Diese müssen jedoch in flexible Strukturen eingebettet werden, die es zu entwickeln gilt. Dafür werden am Ende der Arbeit Handlungsempfehlungen aufgezeigt. / While focussing on the development of existing clusters there is a growing interest in those processes which lead to the emergence of clusters. Those differ from these ones which are typical for a ripe cluster (Bresnahan, Gambardella 2004, p. 842; Henn 2006). Several cases show that policy has an impact on the development of a cluster (z.B. Feldmann et al. 2005, p. 131; Dohse 2000). Though there is a consensus that wishing to stear or initiate a cluster is „wishful thinking“ (Enright 2003, p. 104; Rosenfeld et al. 2006). Entrepreneurs in the surrounding of research institutions are in an advantage commercialising knowledge in new technology fields. This is why regionalised innovation policies are implemented recently, which aim to support this process. The effects and mechanisms of such a spatially focused policy have yet to be clarified (Raines 2002, p. 8; Fromhold-Eisebith, Eisebith 2005, p. 1251; Kiese 3. Oktober 2007). Taking up this question in this thesis the process of emerging clusers is analysed in the field of biotechnology for the cases of Dresden and Leipzig under conditions of post-transformation in Eastern Germany. Further the influence of the complex, regionalised innovation policy of the Free State of Saxony is studied concerning the emgergence of clusters. The aim is to contribute to the discussion on emerging clusters as well as to point out the impact regionalised innovation policy can have. A research model is deduced from theoretical discussion on clusters and regionalised innovation policy. It refers to the multidimensional model of Bathelt (Bathelt 2002) and the relevant dimensions for the emergence process, settlements, learning and founding (Henn 2006). To implement this model among others a mix of semi-structured interviews and social network analysis is used. The analysis shows that “classical” explanations for emerging clusters can not be verified. Founding and settling processes of enterprises seem to be most important. A simple location factor based explanation does not give satisfying answers. Explanations have to take researcher-entrepreneurial networks into account. The analysis shows that the impact of regionalised innovation policy depends on a continual development and evolution of policy in accordance with a changing governance structure in the regional technological surrounding as in the overall region. Monetary support proves to be favourably for spin offs and settlements as well as for entrepreneurial learning processes. Those have to be embedded in flexible and developing governance structures.
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Implementation and quantitative analysis of a real-time sound architecture

Voigt, Michael 16 April 2009 (has links) (PDF)
Several available free software audio solutions were analyzed, and Jackdmp—a C++ reimplementation of the renowned JACK Audio Connection Kit—was selected as the most appropriate solution for a real-time audio architecture on DROPS. The JACK sound architecture provides the lowest processing latency possible on a desktop computer for a given set of sound card parameters. It reduces the latency jitter caused by software to zero and synchronizes streams at sample accuracy. A real-time admission scheme for JACK clients is proposed. The execution time of different typical JACK clients was analyzed with measurements to validate the assumptions the proposal is based on, but also to gain further knowledge about their timing behavior. The measurements showed that the condition set by Paul Davis—the time to process a client must be a linear function of the buffer size—holds for all tested clients. Jackdmp was ported to DROPS. The developed design of the port and its implementation is documented here. Measurements showed that—although the real-time performance of the Linux kernel is continuously being improved in the mainline and on special external branches—DROPS can provide a signaling latency that is two times lower on average than the values that can be achieved on the same machine running with a low latency patched Linux kernel. Thus, it can be stated that DROPS is well-suited for real-time audio processing and that the pursued path to use it as the foundation of a truly real-time capable audio workstation should be followed. / Wenn man heute digitale Audiotechnik zum Aufnehmen oder Abmischen von Musik oder anderen Audiodaten verwenden möchte, steht man vor der Wahl, entweder auf eine sehr spezialisierte Hardwarelösung zurückzugreifen oder aber sich eines gewöhnlichen Desktopsystems mit entsprechender Audiosoftware zu bedienen. Der Vorteil eines Desktopsystems ist neben seinem deutlich niedrigeren Preis vor allem die Flexibilität. Bezüglich seines Echtzeitverhaltens bietet ein Computer mit einem Standard-Desktop-Betriebssystem aber bei weitem nicht dieselbe Verlässlichkeit einer spezialisierten Hardwarelösung oder analoger Technik. Die Architektur von DROPS --- mit dem echtzeitfähigen Fiasco- Mikrokern auf der einen Seite sowie der Unterstützung von Legacy-Anwendungen durch L4Linux auf der anderen Seite --- birgt die Hoffnung, die Vorteile von den beiden eben beschriebenen Welten auf einem System mit DROPS kombinieren zu können. Die Motivation meiner Arbeit war es, für dieses langfristige Ziel einen ersten Grundstein zu legen. Dazu war es meine Aufgabe, verschiedene Open-Source- Lösungen hinsichtlich ihrer Eignung als Echtzeit-Audioarchitektur für DROPS zu analysieren und die am besten geeignete auf L4Env zu portieren. Meine Wahl fiel dabei auf das in der Linux-Audio-Szene wohlbekannte Jack Audio Connection Kit (JACK). Desweiteren konnte ich in der Arbeit untersuchen, wie sich die JACK Audioarchitektur in ein globales Echtzeit-Scheduling --- z.B. eines von DROPS --- einbetten ließe, und schlage eine generische Methode dafür vor.

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