The thesis comprises investigations of two topics related to the PANDA experiment. The first part is dedicated to energy resolution and light yield uniformity studies of PWO crystals for the electromagnetic calorimeter. The second part of the thesis is dedicated to simulation studies of the p̅p→Λ̅Λ and the p̅p→Λ̅Σ0 channels. Photon response measurements with one 3×3 crystals matrix of rectangular crystals and one 5×5 matrix with tapered crystals have been performed at the MAX-Lab synchrotron facility in Lund, Sweden. Photon energies in the range of 13-84 MeV were used. GEANT4 simulations were performed in order to find the most suitable method for adding the energy contributions and for calibration purposes. The widths, σ, of the resulting experimental summed energy peaks were fitted using the Novosibirsk distribution. The results show that the electromagnetic shower at 84 MeV is completely contained in the 5×5 matrix. The widths (σ) for the summed energy peaks were determined.Studies of the uniformity of the light yield were performed for crystals of three different shapes and different wrapping materials. The light yield as a function of distance between the point of energy depositions and the PM tube, was shown to be closely related to the crystal shape and the wrapping material. The p̅p→Λ̅Λ channel was studies at beam momenta of 1.64 GeV/c, 4 GeV/c and 15 GeV/c, while p̅p→Λ̅Σ0 was studied at 4 GeV/c. In the simulations, both phase space differential cross-sections and experimental differential cross-sections from PS185 were used as input. The purpose of the simulations was to show that the reaction channels can be reconstructed in the detector. Special interest was paid to the polarisation and spin correlations of the hyperons. The result is that there is acceptance of cosθ angular range over the full momentum range of the HESR for both channels. Using isotropic differential cross-sections, the polarisation for Λ̅ and Σ0 as well as spin correlations between Λ̅Λ and Λ̅Σ0 can be well reconstructed. Using the differential cross-sections from PS185, the particles are more likely to go forwards in their respective directions in the CM-system, thus making reconstruction over the full angular range more difficult at high beam momenta.

Thirteen N* states have been well-established according to the Particle Data Group, but some relativized quark models predict that many more N* resonances exist. Diquark models predict that the N* spectrum is limited by a correlated quark-pair in the nucleon, but there is strong evidence for the existence of the [Special characters omitted.] (1900)** resonance, which is absent in diquark models. Measuring the spectrum of N* states will provide valuable information on the relevant degrees of freedom within the nucleons. Most of the experimental searches for the N* states have been conducted in the πN channel. Some models of baryon decays predict that most of the unobserved N* states couple somewhat weakly to the πN channel, and that some couple non-negligibly to the KY, K*Y , and KY* channels. Measurements of the cross sections and polarization observables of strangeness photoproduction reactions can provide additional information on the spectrum of N* states. These measurements can be used in coupled-channel partial-wave analyses that can provide simultaneous constraints on the N* resonance parameters from several channels. These analyses can also take into account hadronic rescattering, which is predicted to have a large effect on the measured cross sections. However, to determine the isospin decomposition of the photo-transition amplitudes to these channels, photoproduction measurements are necessary on both the proton and the neutron. Measurements of the differential cross sections of the γn [arrow right] K* (892) 0 Λ and γn [arrow right] K + Σ*(1385) - reactions have been performed using data from the Jefferson Lab Hall B CLAS g13 experiment. No experimental cross section data have yet been published on the γn [arrow right] K* (892) 0 Λ reaction, and the only published cross section data on the γn [arrow right] K + Σ*(1385) - reaction are limited to forward angles, where t -channel K + and K* + exchanges are predicted to dominate. These cross sections are compared against theoretical models to study the channel interactions that give rise to their distributions. These reactions also have the same final state particles ( K + π - pπ - ), so studies of their potential interference were performed as well. A measurement of the γn [arrow right] pπ - cross section was also performed, and the agreement with published results within the uncertainties validated the integrity of the data and procedures used in this analysis.

Bacteriophage Lambda (λ) has played a historical role as an essential model contributing to our current understanding of molecular genetics. Lambda’s major capsid protein “gpD” occurs on each capsid at 405 to 420 copies per phage in homotrimeric form and functions to stabilize the head and likely to compact the genomic DNA. The interesting conformation of this protein allows for its exploitation through the genetic fusion of peptides or proteins to either the amino or carboxy terminal end of gpD, while retaining phage assembly functionality and viability. The lytic nature of λ and the conformation of gpD in capsid assembly makes this display system superior to other display options. Despite previous reports of λ as a phage display candidate, decorative control of the phage remains an elusive concept. The primary goal of this study was to design and construct a highly controllable head decoration system governed by two genetic conditional regulation systems; plasmid-mediated temperature sensitive repressor expression and bacterial conditional amber mutation suppression. The historical λ Dam15 conditional allele results in a truncated gpD fragment when translated in nonsuppressor, wild-type E. coli cells, resulting in unassembled, nonviable progeny. I sequenced the Dam15 allele, identifying an amber (UAG) translational stop at the 68th codon. Employing this mutant in combination with a newly created isogenic cellular background utilizing the amber suppressors SupD (Serine), SupE (Glutamine), SupF (Tyrosine) and Sup— (wild type), we sought to control the level of incorporation of undecorated gpD products. As a second dimension, I constructed two separate temperature-inducile plasmids whereby expression of either D or D::eGFP was governed by the λ strong λ CI[Ts]857 temperature-sensitive repressor and expressed from the λ PL strong promoter. Our aim was to measure the decoration of the λ capsid by a D::gfp fusion under varying conditions regulated by both temperature and presence of suppression. This was achieved utilizing this controllable system, enabling the measurement of a variable number of fusions per phage based on diverse genetic and physical environments without significantly compromising phage viability. Surprisingly, both SupE and SupF showed similar levels of Dam15 suppression, even though sequencing data indicated that only SupE could restore the native gpD sequence at amino acid 68 (Q). In contrast, SupD (S), conferred very weak levels of suppression, but imparted an environment for very high decoration of gpD::eGFP per capsid, even at lower (repressed) temperatures. The presence of albeit few wild-type gpD molecules allowed for an even greater display than that of the perceived “100%” decoration scenario provided by the nonsuppressor strain. It appears that the lack of wild-type gpD does not allow for the space required to display the maximum number of fusions and in turn creates an environment that affects both phage assembly and therefore phage viability. Finally, the use of Western blotting, confirmed the presence of gpD::eGFP fusion decoration by employing a polyclonal anti-eGFP antibody. The significance of this work relates to the unique structure of λ’s capsid and its ability to exploit gpD in the design of controlled expression, which is guiding future research examining the fusion of different therapeutic peptides and proteins. Furthermore this approach has important implications specifically for the design of novel vaccines and delivery vehicles for targeted gene therapy in which steric hindrance and avidity are important concerns. The execution of this project employed basic bacterial genetics, phage biology and molecular biology techniques in the construction of bacterial strains and plasmids and the characterization of the phage display system.

Contrôler la consommation en ressources des programmes informatiques est d'importance capitale, non seulement pour des raisons de performance, mais aussi pour des questions de sécurité quand par exemple certains systèmes mobiles ou embarqués disposent de quantités limitées de ressources. Dans cette thèse, nous développons des critères statiques pour contrôler la consommation en ressources de programmes concurrents d'ordre supérieur. Nous prenons comme point de départ le cadre des Logiques Light qui a été étudié afin de contrôler la complexité de programmes fonctionnels d'ordre supérieur au moyen de la correspondance preuves-programmes. La contribution de cette thèse est d'étendre ce cadre aux programmes concurrents d'ordre supérieur. Plus généralement, cette thèse s'inscrit dans le domaine de la complexité implicite qui cherche à caractériser des classes de complexité par des principes logiques ou des restrictions de langage. Les critères que nous proposons sont purement syntaxiques et sont développés graduellement afin de contrôler le temps de calcul des programmes de plus en plus finement: dans un premier temps nous montrons comment garantir la terminaison des programmes (temps fini), puis nous montrons comment garantir la terminaison des programmes en temps élémentaire, et enfin nous montrons comment garantir la terminaison des programmes en temps polynomial. Nous introduisons également des systèmes de types tels que les programmes bien typés terminent en temps borné et retournent des valeurs. Enfin, nous montrons que ces systèmes de types capturent des programmes concurrents intéressants qui itèrent des fonctions produisant des effets de bord sur des structures de données inductives. Dans la dernière partie, nous étudions une méthode sémantique alternative afin de contrôler la consommation en ressources de programmes impératifs d'ordre supérieur. Cette méthode est basée sur la réalisabilité quantitative de Dal Lago et Hofmann et permet d'obtenir plusieurs bornes de complexité de manière uniforme. Cette dernière partie est un travail en collaboration avec Aloïs Brunel.

The interplay between spectrum and structure of graphs is the recurring theme of the three more or less independent chapters of this thesis. The first chapter provides a method to relate the eigensolutions of two matrices, one being the principal submatrix of the other, via an arbitrary annihilating polynomial. This is extended to lambda-matrices and to matrices the entries of which are rational functions in one variable. The extension may be interpreted as a possible generalization of other known techniques which aim at reducing the size of a matrix while preserving the spectral information. Several aspects of an application in order to reduce the computational costs of ordinary eigenvalue problems are discussed. The second chapter considers the straightforward extension of the well known concept of equitable partitions to weighted graphs, i.e. complex matrices. It provides a method to divide the eigenproblem into smaller parts corresponding to the front divisor and its complementary factor in an easy and stable way with complexity which is only quadratic in matrix size. The exploitation of several equitable partitions ordered by refinement is discussed and a suggestion is made that preserves hermiticity if present. Some generalizations of equitable partitions are considered and a basic procedure for finding an equitable partition of complex matrices is given. The third chapter deals with isospectral and unitary equivalent graphs. It introduces a construction for unitary equivalent graphs which contains the well known GM-switching as a special case. It also considers an algebra of graph matrices generated by the adjacency matrix that corresponds to the 1-dimensional Weisfeiler-Lehman stabilizer in a way that mimics the correspondence of the coherent closure and the 2-dimensional Weisfeiler-Lehman stabilizer. The algebra contains the degree matrix, the (combinatorial, signless and normalized) Laplacian and the Seidel matrix. An easy construction produces graph pairs that are simultaneously unitary equivalent w.r.t. that algebra.

Emission from cars today is one of the biggest environmental issues, hence stringent government standards have been introduced to decrease emission. Car companies do not only have to satisfy government standards, but also meet consumer demands on increased fuel economy and good drivablility. This report will introduce controllers designed to control the air/fuel ratio in an SI engine. The engine model used is simplified. The engine components modelled include the inlet manifold, fuel dynamics, combustion and exhaust sensor. Nonlinearities and delays are inherent in the engine dynamics and as such a Smith Predictor is utilised as the basis for controller structure to compensate for the delays. Here the Smith Predictor is combined with feedforwarding of the mass air charge, which is estimated from both the inlet and combustion models. Therefore different ways of merging the estimates are also explored. A real engine was not accesible, thus simulators were implemented using data sets provided by General Motors. Model errors were introduced to test the controllers performance. The proposed methods should be tested on a real engine to ensure that this isa viable approach, as the simulations show it maybe promising to use in practice.

Due to stricter emission legislation, there is a need for more efficient control of diesel engines with exhaust gas recirculation(EGR). In particular, it is important to estimate the air/fuel ratio accurately in transients. Therefore a new engine gas flow model has been developed. This model divides the gas into one part for oxygen and one part for inert gases. Based on this model an observer has been designed to estimate the oxygen concentration in the gas going into the engine, which can be used to calculate the air/fuel ratio. This observer can also be used to estimate the intake manifold pressure. The advantage of estimating the pressure, instead of low pass filtering the noisy signal, is that the observer does not cause time delay.

Die Herleitung des Unterschieds zwischen globaler und lokaler Stöchiometriezahl für den Oxyfuel-Prozess hat gezeigt, dass gleiche lokale Stöchiometriezahlen bei variierendem Rezirkulationsanteil unterschiedliche globale Stöchiometriezahlen zur Folge haben. In dieser Arbeit wird vorgeschlagen, die Bezeichnung der Zustandspunkte im Oxyfuel-Prozess mit den Sauerstoffkonzentrationen am Brennkammereintritt bzw. -austritt zu verbinden. Für den Sauerstoffanteil am Brennkammereintritt (z.B. 30 vol.-%) und den Restsauerstoff am Brennkammerende (z.B. 4 vol.-%) folgt zum Bespiel die Bezeichnung Oxyfuel 30 mit 4 % Restsauerstoff. Diese Bezeichnung ist eindeutig und kann das Lambda – als Beschreibung der Stöchiometrie im konventionellen Betrieb – ablösen. Für eine Vielzahl an Punkten sind Verbrennungsversuche mit Trockenbraunkohle und Sauerstoff durchgeführt worden. Ein stabiler Betrieb der Versuchsanlage der TU Dresden wurde zwischen Oxyfuel 17 und Oxyfuel 33 erreicht. Die Untersuchungen haben nachgewiesen, dass die Rezirkulation des feuchten Abgases für die Verbrennung unkritisch ist. Die Schwefeldioxid-Emissionen sind abhängig von den variierenden Reaktionstemperaturen im Kennfeld, dem Restsauerstoff am Brennkammerende und der Rezirkulation des Abgases. Mit der Belagssondenmessung von Aschepartikeln im Abgasstrom wurde gezeigt, dass auch andere Komponenten (z.B. Chlor) im Oxyfuel-Prozess aufkonzentriert werden. Diese erhöhten Konzentrationen werden zu neuen Anforderungen in der Werkstoffauswahl führen. Für das Einschwingverhalten der Abgaszusammensetzung beim Umschalten von konventioneller Verbrennung zu Oxyfuel-Prozess-Fahrweise hat sich gezeigt, dass für diese Staubfeuerungs-Versuchsanlage ein einfaches Rührkesselmodell geeignet ist.

Ces dernières années, on a assisté au développement du<br />calcul de réécriture, encore appelé rho-calcul, qui intègre de<br />façon uniforme la réécriture de premier ordre et le lambda-calcul.<br />Cette thèse est dédiée à l'étude des capacités d'expression du calcul de réécriture, avec un intérêt particulier pour la réécriture d'ordre supérieur et la possibilité de manipuler des graphes.<br /><br />Dans la première partie de cette thèse, la relation entre le calcul de réécriture et la réécriture d'ordre supérieur, en particulier les Combinatory Reduction Systems (CRSs), est étudiée.<br />Nous présentons d'abord un algorithme de filtrage original<br />pour les CRSs qui utilise une traduction des termes CRS en<br />lambda-termes et le filtrage d'ordre supérieur classique du lambda-calcul. Nous proposons ensuite un encodage des CRSs dans le rho-calcul<br />basé sur la traduction de chaque réduction CRS<br />en une réduction correspondante dans le rho-calcul.<br />Dans la deuxième partie, nous présentons une extension du rho-calcul,<br />appelé calcul de réécriture de graphes (ou Rg-calcul),<br />qui gère des termes avec partage et cycles.<br />Le calcul sur les termes est généralisé de manière naturelle en utilisant des contraintes d'unification en plus des contraintes de filtrage standard du rho-calcul.<br /><br />Le Rg-calcul est alors montré confluent sur des classes<br />d'équivalence de termes, sous certaines restrictions de linéarité sur les motifs, et assez<br />expressif pour simuler la réécriture de termes graphes et le<br />lambda-calcul cyclique.

Nous étudions les propriétés, en particulier la terminaison, des systèmes de types dépendants pour le lambda-calcul et la réécriture.