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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.
161

New object grasp synthesis with gripper selection: process development

Legrand, Tanguy January 2022 (has links)
A fundamental aspect to consider in factories is the transportation of the items at differentsteps in the production process. Conveyor belts do a great to bring items from point A topoint B but to load the item onto a working station it can demands a more precise and,in some cases, delicate approach. Nowadays this part is mostly handled by robotic arms.The issue encountered is that a robot arm extremity, its gripper, cannot directly instinctivelyknow how to grip an object. It is usually up to a technician to configure how andwhere the gripper goes to grip an item.The goal of this thesis is to analyse a problem given by a company which is to find a wayto automate the grasp pose synthesis of a new object with the adapted gripper.This automatized process can be separated into two sub-problems.First, how to choose the adapted gripper for a new object.Second, how to find a grasp pose on the object, with the previously chosen gripper.In the problem given by the company, the computer-aided design (CAD) 3D model of theconcerned object is given. Also, the grasp shall always be done vertically, i.e., the grippercomes vertically to the object and the gripper does not rotate on the x and y axis. Thegripper for a new object is selected between two kinds of grippers: two-finger paralleljawgripper and three-finger parallel-jaw gripper. No dataset of objects is provided.Object grasping is a well researched subject, especially for 2 finger grippers. However,few research is done for the 3 finger grippers grasp pose synthesis, or for gripper comparison,which are key part of the studied problem.To answer the sub-problems mentioned above, machine learning will be used for the gripperselection and a grasp synthesis method will be used for the grasp pose finding. However,due to the lack of gripper comparison in the related work, a new approach needsto be created, which will be inspired by the findings in the literature about grasp posesynthesis in general.This approach will consist of two parts.First, for each gripper and each object combination are generated some grasp poses, eachassociated with a corresponding score. The scores are used to have an idea of the bestgripper for an object, the best score for each gripper indicating how good a grasp couldbe on the object with said gripper.Secondly, the objects with their associated best score for each gripper will be used astraining data for a machine learning algorithm that will assist in the choice of the gripper.This approach leads to two research questions:“How to generate grasps of satisfying quality for an object with a certain gripper?”“Is it possible to determine the best gripper for a new object via machine learning ?”The first question is answered by using mathematical operations on the point cloud representationof the objects, and a cost function (that will be used to attribute a score), whileithe second question is answered using machine learning classification and regression togain insight on how machine learning can learn to associate object proprieties to gripperefficiency.The found results show that the grasp generation with the chosen cost function givesgrasp poses that are similar to the grasp poses a human operator would choose, but themachine learning models seem unable to assess grasp quality, either with regression orclassification.
162

Die aard van kommunikasie in ʼn sosiale betrokkenheidsprogram van die Studente-Jool-Gemeenskapsdiens (SJGD) : die Pick a leader- leierskapontwikkelingsprojek / Johanna Frederika Elizabeth Boshoff

Boshoff, Johanna Frederika Elizabeth January 2013 (has links)
The North-West University (NWU) is an example of an organization that has a social responsibity towards the community and the environment within which it finds itself (Van Schalkwyk, 2013). One of the social responsibility programmes of the NWU-Pukke is known as the Students’ Rag Community Service (SRCS). The SRCS is a registered NPO (non-profit organization) which is run by the students of the NWU Potchefstroom Campus and which has been in existence since 1992 in its present form. In this study it is argued that the SRCS developmental projects could be offered in a more effective and sustainable manner by implementing the basic principles of the participatory approach, viz. Participation, dialogue, empowerment and cultural identity in order to support the local communities in their developmental processes. For the present study the focus was solely on one of the SRCS projects, the Pick a leader-leadership development project. This project has the aim of providing in the developmental needs of ten to fifteen Grade 11 learners in three schools in the North West Province (Potchefstrom and the surrounding communities in Ikageng). Thus project participants (learners) are instructed in basic skills about starting their own businesses (entrepreneurship); how to develop their leadership skills and to apply these skills, and how to be able to use basic life skills in their everyday lives. Various theoreticians have explained how NPO’s without participatory communication are seldom successful in terms of developmental initiatives. The learners can only develop if the relevant roleplayers of the project take ownership of the project by also being able to communicate in a participatory manner about their specific needs with both the NPO and the project volunteers. The NWU-Pukke volunteers, who manage this particular project, therefore have the responsibility to communicate in a participatory manner with the relevant learners, their teachers and then also the different principals to make the project succeed and to contribute to the realization of the developmental needs of the learners. The general research aim of the study had been to determine the nature of the communication among interest groups in the Pick a leader-leadership development programme of the SRCS. Qualitiative research methods, viz. Semi-structured interviews, focus group interviews and participant observation, were used in this study for purposes of making making a thorough investigation into the nature of the communication among those involved in the Pick a leader leadership development programme. The purpose of this was to determine perspectives about the project held by the persons involved (but especially those of the learners) and to interpret these in line with the normative theoretical principles of the participatory approach to developmental communication. It was ultimately found that the communication in the Pick a leader-leadership development programme was mostly one-way. / MA (Communication Studies), North-West University, Potchefstroom Campus, 2014
163

Arbetsrätten vid partiella företagsförvärv : Med utgångspunkt i förvärvsmetodernas skatterättsliga följder / Labour law in the context of partial corporate acquisitions : based on the taxative consequences of the acquisition methods

Jonsson, Andreas, Maslyannikov, Lev January 2015 (has links)
Företagsförvärv ger ofta upphov till arbetsrättsliga och skatterättsliga frågor där många människor och stora belopp är inblandade. I samband med partiella företagsförvärv ställs dessa frågor på sin spets, i och med att svåra gränsdragningar måste göras när ett bolag delas upp. Dessa gränsdragningar görs dessutom på olika grunder i olika rättsområden. Ur ett ekonomiskt perspektiv kan en misslyckad personalövergång innebära stora kostnader samt risker för konflikter. En skatterättsligt oförmånlig utgång är också kostsam. Av den anledningen har vi, i denna uppsats, valt att lägga fokus på arbetsrättsliga och skatterättsliga frågor vid partiella företagsförvärv. Dessa frågor behandlas på följande sätt. Först görs en genomgång av relevanta rättsregler inom arbetsrätt, skatterätt och bolagsrätt, för att måla upp en någorlunda nyanserad bild av både den arbetsrättsliga bedömningsgången och de skatterättsliga och bolagsrättsliga ramar inom vilka förvärvsmetoderna ligger. Mot denna bakgrund har vi valt att ställa upp tre exempel som illustrerar hur metoderna kan tillämpas för att uppnå olika arbetsrättsliga effekter. Exemplen är utformade för att täcka flertalet av de regelverk som har utretts i uppsatsens första del. Slutligen görs en samlad utvärdering av resultaten. Själva förvärvsmetoden i sig sätter upp ramarna inom vilka arbetsrätten kan tillämpas, men det är den önskade arbetsrättsliga följden som styr valet av förvärvsmetod och dess utformning. Önskade följder vad gäller arbetstagare kan uppnås samtidigt som en skatterättsligt förmånlig behandling är möjlig. Genomförandet av ett partiellt företagsförvärv, med beaktande av skatterättsliga former och arbetsrättsliga följder, kan således innebära en lyckad ”cherry-pick”. / Corporate acquisitions often give rise to questions pertaining labour law and tax law, where many people and large amounts of money are involved. In the context of partial acquisitions, these questions come to a head, since difficult delimitations must be done when dividing a company. These delimitations are, furthermore, based upon different grounds within different fields of law. From an economical perspective, a failed transition of staff can carry considerable costs and risks of conflict. A disadvantageous outcome in the context of tax law is expensive as well. For this reason we have chosen, in this thesis, to focus on questions concerning labour law and tax law in the context of partial corporate acquisitions. These questions are treated in the following manner. Firstly, a review of the relevant norms within labour law, tax law and corporate law is made. This is done to paint a somewhat nuanced picture of both the assessment process within labour law and the frames of tax and company law, in which the methods of acquisition are stipulated. Against this background, we have constructed three examples that illustrate how the methods can be applied to achieve different effects pertaining labour law. The examples are designed to cover the majority of the norms that were investigated in the first part of the thesis. Finally, a general evaluation of the results is made. The method of acquisition, by itself, erects a framework in which labour law can be applied. However, it is the desired outcome in the context of labour law that governs the choice of acquisition method and its arrangement. It is possible to achieve these desired outcomes while receiving an advantageous treatment in the context of tax law as well. The execution of a partial acquisition, with consideration for the methods within tax law and the results within labour law, can therefore amount to a successful ”cherry pick”.
164

Die aard van kommunikasie in ʼn sosiale betrokkenheidsprogram van die Studente-Jool-Gemeenskapsdiens (SJGD) : die Pick a leader- leierskapontwikkelingsprojek / Johanna Frederika Elizabeth Boshoff

Boshoff, Johanna Frederika Elizabeth January 2013 (has links)
The North-West University (NWU) is an example of an organization that has a social responsibity towards the community and the environment within which it finds itself (Van Schalkwyk, 2013). One of the social responsibility programmes of the NWU-Pukke is known as the Students’ Rag Community Service (SRCS). The SRCS is a registered NPO (non-profit organization) which is run by the students of the NWU Potchefstroom Campus and which has been in existence since 1992 in its present form. In this study it is argued that the SRCS developmental projects could be offered in a more effective and sustainable manner by implementing the basic principles of the participatory approach, viz. Participation, dialogue, empowerment and cultural identity in order to support the local communities in their developmental processes. For the present study the focus was solely on one of the SRCS projects, the Pick a leader-leadership development project. This project has the aim of providing in the developmental needs of ten to fifteen Grade 11 learners in three schools in the North West Province (Potchefstrom and the surrounding communities in Ikageng). Thus project participants (learners) are instructed in basic skills about starting their own businesses (entrepreneurship); how to develop their leadership skills and to apply these skills, and how to be able to use basic life skills in their everyday lives. Various theoreticians have explained how NPO’s without participatory communication are seldom successful in terms of developmental initiatives. The learners can only develop if the relevant roleplayers of the project take ownership of the project by also being able to communicate in a participatory manner about their specific needs with both the NPO and the project volunteers. The NWU-Pukke volunteers, who manage this particular project, therefore have the responsibility to communicate in a participatory manner with the relevant learners, their teachers and then also the different principals to make the project succeed and to contribute to the realization of the developmental needs of the learners. The general research aim of the study had been to determine the nature of the communication among interest groups in the Pick a leader-leadership development programme of the SRCS. Qualitiative research methods, viz. Semi-structured interviews, focus group interviews and participant observation, were used in this study for purposes of making making a thorough investigation into the nature of the communication among those involved in the Pick a leader leadership development programme. The purpose of this was to determine perspectives about the project held by the persons involved (but especially those of the learners) and to interpret these in line with the normative theoretical principles of the participatory approach to developmental communication. It was ultimately found that the communication in the Pick a leader-leadership development programme was mostly one-way. / MA (Communication Studies), North-West University, Potchefstroom Campus, 2014
165

Synthese von Inositderivaten für die Manipulation von Sphingolipid-metabolisierenden Enzymen

Prause, Kevin 12 February 2024 (has links)
Ceramid, ein zentrales Signalmolekül des Sphingolipidstoffwechsels, ist neben der de novo Synthese über die enzymatische Spaltung von Sphingomyelin und Glucosylceramid zugänglich. Genetische Mutationen, die eine Fehlfaltung der verantwortlichen Enzyme saure Sphingomyelinase (aSMase) und Glucocerebrosidase (GCase) begünstigen, könnten somit zu einer Dysregulation des gesamten Sphingolipidstoffwechsels und den damit verbundenen Signaltransduktionsprozessen führen. Niedermolekulare Inhibitoren können in Zellstudien einen Einblick in diese Prozesse geben und den Defekt eines Enzyms simulieren oder eine etwaige Überaktivität derselben Enzyme verhindern. Für derartige Studien ist die Möglichkeit einer zeitaufgelösten Inhibition von Vorteil. Für diese Methode müssten photolabile Schutzgruppen in eine bereits bekannte Inhibitorstruktur integriert werden. Im Fall der aSMase würden sich hierfür myo-Inosit-bisphosphat-Derivate anbieten, die starke, kompetitive Inhibitoren des Enzyms darstellen. Auf dieser Grundlage werden in der vorliegenden Arbeit die Synthese sowie die in vitro und in cellulo Wirkung des ersten zellpermeablen, photoaktivierbaren Inhibitors für die aSMase präsentiert. Kompetitive Inhibitoren können ebenso als sogenannte pharmakologische Chaperone fungieren, welche Proteine durch Herabsetzung der freien Energie des jeweiligen Faltungszustandes stabilisieren. Dies ist besonders bei von Mutationen betroffenen lysosomalen Enzymen von Interesse, um diese vor einem proteasomalen Abbau zu bewahren und einen geregelten Transport in die Lysosomen zu gewährleisten. So wurden in der vorliegenden Arbeit verschiedene myo-Inositderivate als potenzielle pharmakologische Chaperone für die aSMase und GCase synthetisiert. Um eine Verdrängung der Verbindungen vom aktiven Zentrum des Enzyms durch das natürliche Substrat zu beschleunigen, wurde eine Orthoesterfunktion in die Seitenkette der Inhibitorstruktur integriert, die im sauren Milieu der Lysosomen gespalten werden kann. / Ceramide, a central signaling molecule in sphingolipid metabolism, is in addition to the novo synthesis accessible via the enzymatic cleavage of sphingomyelin and glucosylceramide. Genetic mutations that promote misfolding of the responsible enzymes acid sphingomyelinase (aSMase) and glucocerebrosidase (GCase) could thus lead to a dysregulation of the entire sphingolipid metabolism and the associated signal transduction processes. Small molecule inhibitors can provide insight into these processes in cell studies and simulate the defect of an enzyme or prevent eventual overactivity of the same enzyme. For such studies, the possibility of a time-resolved inhibition would be advantageous. For this method, photolabile protecting groups would have to be integrated into the structure of a known inhibitor. In the case of aSMase, myo-inositol-diphosphate derivatives, which represent strong, competitive inhibitors of the enzyme, would be suitable for this purpose. On this basis, the synthesis as well as the in vitro and in cellulo effects of the first cell-permeable photocaged inhibitor for acid sphingomyelinase are presented in this work. Competitive inhibitors can also act as so-called pharmacological chaperones, which stabilize proteins by reducing the free energy of the respective folding state. This is of particular interest in the case of lysosomal enzymes affected by mutations, in order to protect them from proteasomal degradation and to ensure regulated transport into the lysosomes. In the present work, various myo-inositol derivatives were synthesized as potential pharmacological chaperones for aSMase and GCase. To accelerate displacement of the compounds from the enzyme's active site by the natural substrate, an orthoester function was integrated into the side chain of the inhibitor structure, which can be cleaved in the acidic environment of the lysosome.
166

Molekulárně genetická analýza u Niemann-Pickovy choroby typu C / Molecular genetic analysis in Niemann-Pick type C disease

Marešová, Ivona January 2013 (has links)
Niemann-Pick disease type C (NPC) is a rare, severe disease with autosomal recessive inheritance. Disease is caused by pathogenic mutations located in genes NPC1/NPC2. These genes encode lysosomal non enzymatic NPC1/NPC2 proteins that are part of lipid transport. As a result of malfunction of these proteins intracellular accumulation of lipids occurs, in particular free cholesterol and glycolipids. Causal therapy is currently still unsatisfactory therefore new therapies are evolved. However these therapies depend on whether the patient cells contain at least residual amount of transcript NPC1 gene. In a group of patiens, for which a fibroblast culture was available, I analyzed the effect of pathogenic mutations on the expression level of the transcript. Results showed that for all pathogenic mutations transcript level is low, but detectable. Moreover, I characterized the structure of the NPC1 gene promoter. By sequence analysis I found polymorphisms rs8099071, rs28403610, rs2981422, rs1652354, rs1788774, rs1788772 in promoter. On the basis of the composition of polymorphisms in individual patiens, I estimate six different haplotypes. I performed mutation analysis in DNA of recently diagnosed patient. I found only one pathogenic mutation p.I1061T (c.3182T> C) in the NPC1 gene. Therefore I tested...
167

A flexible coil array for high resolution magnetic resonance imaging at 7 Tesla / Réseau flexible d'antennes miniatures pour l'imagerie par résonance magnétique haute résolution à 7 Tesla

Kriegl, Roberta 17 December 2014 (has links)
L’imagerie par résonance magnétique (IRM) est un outil d’investigation majeur donnant accès de manière non invasive à des nombreuses informations quantitatives et fonctionnelles. La qualité des images obtenues (rapport-signal-sur-bruit, RSB) est cependant limitée dans certaines applications nécessitant des résolutions spatiales et/ou temporelles poussées. Afin d’améliorer la sensibilité de détection des équipements d’IRM, diverses orientations peuvent être suivies telles qu’augmenter l’intensité du champ magnétique des imageurs, améliorer les performances des systèmes de détection radiofréquence (RF), ou encore développer des séquences d’acquisition et des techniques de reconstruction d’images plus efficaces. La thématique globale dans laquelle s’inscrit cette thèse concerne le développement des systèmes de détection RF à haute sensibilité pour l’IRM à haut champ chez l’homme. En particulier, des antennes auto-résonantes basées sur le principe des lignes de transmission sont utilisées parce qu’elles peuvent être réalisée sur substrat souple. Cette adaptabilité géométrique du résonateur permet d’ajuster précisément sa forme aux spécificités morphologiques de la zone anatomique observée, et ainsi d’augmenter le RSB. La première visée technologique de ce projet concerne le développement, de la conception jusqu’à la mise en œuvre dans un appareil 7 T corps entier, d’un système de détection RF flexible à haute sensibilité, utilisant des antennes miniatures associées en réseau. L’utilisation d’un réseau d’antennes miniatures permet d’obtenir des images sur un champ de vue élargi tout en conservant la haute sensibilité inhérente à chaque antenne miniature. De plus, la technologie de l’imagerie parallèle devient accessible, ce qui permet d’accélérer l’acquisition des images. De surcroît, un nouveau schéma de résonateur de ligne transmission avec un degré de liberté supplémentaire est introduit, ce qui permet de réaliser de grands résonateurs multi-tours pour l’IRM à haut champ. Cette thèse décrit le développement, la mise en œuvre et l’évaluation des nouveaux systèmes de détection RF au moyen de simulations analytiques et numériques, et des études expérimentales. / Magnetic resonance imaging (MRI), among other imaging techniques, has become a major backbone of modern medical diagnostics. MRI enables the non-invasive combined, identification of anatomical structures, functional and chemical properties, especially in soft tissues. Nonetheless, applications requiring very high spatial and/or temporal resolution are often limited by the available signal-to-noise ratio (SNR) in MR experiments. Since first clinical applications, image quality in MRI has been constantly improved by applying one or several of the following strategies: increasing the static magnetic field strength, improvement of the radiofrequency (RF) detection system, development of specialized acquisition sequences and optimization of image reconstruction techniques. This work is concerned with the development of highly sensitive RF detection systems for biomedical ultra-high field MRI. In particular, auto-resonant RF coils based on transmission line technology are investigated. These resonators may be fabricated on flexible substrate which enables form-fitting of the RF detector to the target anatomy, leading to a significant SNR gain. The main objective of this work is the development of a flexible RF coil array for high-resolution MRI on a human whole-body 7 T MR scanner. With coil arrays, the intrinsically high SNR of small surface coils may be exploited for an extended field of view. Further, parallel imaging techniques are accessible with RF array technology, allowing acceleration of the image acquisition. Secondly, in this PhD project a novel design for transmission line resonators is developed, that brings an additional degree of freedom in geometric design and enables the fabrication of large multi-turn resonators for high field MR applications. This thesis describes the development, successful implementation and evaluation of novel, mechanically flexible RF devices by analytical and 3D electromagnetic simulations, in bench measurements and in MRI experiments.
168

Estudo da reação (d,t) nos isótopos 100, 102 e 104 do rutênio / Reaction (d, t) study on 100, 102, 104 Ru

Duarte, Jose Luciano Miranda 21 August 1991 (has links)
Componentes de buraco de nêutrons nos isótopos ANTPOT 99, 101, 103 Ru foram investigadas atrav6s de reações (d,t), induzidas por dêuterons de 15,5 MeV em ANTPOT 100Ru e 16 MeV em ANTPOT 102 Ru e ANTPOT 101 Ru. Os grupos de trítons emergentes, analisados em momento por um espectrógrafo magnético, foram detectados em placas de emulsão nuclear. Resolução em energia melhor que 8 keV permitiu a identificação de 14, 36 e 46 níveis, até as energias de excitação de 1,4; 2,1 e 2,5 MeV, respectivamente, nos ANTPOT 99, 101, 103 Ru. Os momentos angulares orbitais transferidos, l, e as intensidades espectroscópicas foram obtidos a partir da comparação entre distribuições angulares experimentais, medidas cm ângulos judiriosamente escolhidos entre 8º e 46º, e as previstas pela Aproximação de Born com Ondas Distorcidas. A análise das distribuições das intensidades espectroscópicas, associadas a cada l, nos três isótopos revela um padrão de semelhança, embora haja um deslocamento das maiores intensidades espectroscópicas para menores energias, quando se eleva o número de nêutrons, que indica, juntamente com um aumento da densidade de níveis, crescente deformação nuclear. Especial atenção é dirigida a transições para estados de baixa energia de excitação com l = 3 e l = 1, associadas a orbitais não pertencentes à camada de valência, cuja descrição é discutida em termos de um modelo quase-partícula-rotor prolato, não-rígido, com o tratamento completo da interação de Coriolis, e do Modelo de Bósons e Férmions Interatuantes. / Neutron-hole components in 99, 101, 103 Ru Isotopes were Investigated by (d,t) reactions at incident deuteron energies of 15.5 MeV and 16 MeV on, respectively, 100 Ru and 102,104 Ru. Outgoing triton groups were momentum analyzed by a magnetic spectrograph and dctectcd in nuclear emulsion plates with an energy resolution better than 8 keV. A total of 14, 36 and 46 leveis up to 1.4, 2.1 and 2.5 MeV excitation energy were identified, respectively, 99, 101, 103 Ru. The transferred orbital angular momenta, l, and the spectroscopic strengths were obtained by con1paring experimental angular distributions, measured at carefully chosen scattering angles between 8º and 46º, with Distorted Wave Born Approximation predictions. The analysis of the spectroscopic strength distributions corresponding to each l-value reveals a similar pattern among the three isotopes, although there is a shift of the highest strengths towards low energy, for increasing neutron number, indicating increasing deform at ion. Special attention is drawn to transitions to low-lying states with l=3 and l=1 character, associated with the next major shell, whose description is discussed in terms of a quasiparticle-prolate non-rigid rotor model with the Coriolis effect fully treated, and the Interacting Boson-Fermion Model.
169

Estudo da reação (d,t) nos isótopos 100, 102 e 104 do rutênio / Reaction (d, t) study on 100, 102, 104 Ru

Jose Luciano Miranda Duarte 21 August 1991 (has links)
Componentes de buraco de nêutrons nos isótopos ANTPOT 99, 101, 103 Ru foram investigadas atrav6s de reações (d,t), induzidas por dêuterons de 15,5 MeV em ANTPOT 100Ru e 16 MeV em ANTPOT 102 Ru e ANTPOT 101 Ru. Os grupos de trítons emergentes, analisados em momento por um espectrógrafo magnético, foram detectados em placas de emulsão nuclear. Resolução em energia melhor que 8 keV permitiu a identificação de 14, 36 e 46 níveis, até as energias de excitação de 1,4; 2,1 e 2,5 MeV, respectivamente, nos ANTPOT 99, 101, 103 Ru. Os momentos angulares orbitais transferidos, l, e as intensidades espectroscópicas foram obtidos a partir da comparação entre distribuições angulares experimentais, medidas cm ângulos judiriosamente escolhidos entre 8º e 46º, e as previstas pela Aproximação de Born com Ondas Distorcidas. A análise das distribuições das intensidades espectroscópicas, associadas a cada l, nos três isótopos revela um padrão de semelhança, embora haja um deslocamento das maiores intensidades espectroscópicas para menores energias, quando se eleva o número de nêutrons, que indica, juntamente com um aumento da densidade de níveis, crescente deformação nuclear. Especial atenção é dirigida a transições para estados de baixa energia de excitação com l = 3 e l = 1, associadas a orbitais não pertencentes à camada de valência, cuja descrição é discutida em termos de um modelo quase-partícula-rotor prolato, não-rígido, com o tratamento completo da interação de Coriolis, e do Modelo de Bósons e Férmions Interatuantes. / Neutron-hole components in 99, 101, 103 Ru Isotopes were Investigated by (d,t) reactions at incident deuteron energies of 15.5 MeV and 16 MeV on, respectively, 100 Ru and 102,104 Ru. Outgoing triton groups were momentum analyzed by a magnetic spectrograph and dctectcd in nuclear emulsion plates with an energy resolution better than 8 keV. A total of 14, 36 and 46 leveis up to 1.4, 2.1 and 2.5 MeV excitation energy were identified, respectively, 99, 101, 103 Ru. The transferred orbital angular momenta, l, and the spectroscopic strengths were obtained by con1paring experimental angular distributions, measured at carefully chosen scattering angles between 8º and 46º, with Distorted Wave Born Approximation predictions. The analysis of the spectroscopic strength distributions corresponding to each l-value reveals a similar pattern among the three isotopes, although there is a shift of the highest strengths towards low energy, for increasing neutron number, indicating increasing deform at ion. Special attention is drawn to transitions to low-lying states with l=3 and l=1 character, associated with the next major shell, whose description is discussed in terms of a quasiparticle-prolate non-rigid rotor model with the Coriolis effect fully treated, and the Interacting Boson-Fermion Model.
170

Beitrag zur Optimierung der Verfahrensparameter von Vliesstoffausrüstungsprozessen bei hohen Warengeschwindigkeiten / Contribution to optimisation of process parameters of nonwoven finishing processes at high speeds

Grönke, Kerstin 15 December 2014 (has links) (PDF)
Gegenstand der vorliegenden Arbeit ist die Untersuchung des Foulardierprozesses zur chemischen Nassausrüstung von Vliesstoffen bei Warengeschwindigkeiten bis zu 250 m/min. Hintergrund ist die abweisende Ausrüstung von Polypropylen-Spinnvliesstoffen für die Anwendung als Operationskittel. Wo bislang nach dem Stand der Technik eine Veredlung bei Lohnausrüstern bei geringen Warengeschwindigkeiten durchgeführt wurde, zeigt die Tendenz in der Vliesstoffindustrie in Richtung der eigenen Prozessbeherrschung. Eine grundlegende Voraussetzung, um den Foulardierprozess für diese Anwendung nutzbar zu machen, ist die Kenntnis über die Prozesseigenschaften bei den geforderten hohen Warengeschwindigkeiten. Für den abzudeckenden Versuchsraum mit sechs Einflussgrößen bei jeweils drei Faktorstufen wurde mittels der Methodik der statistischen Versuchsplanung ein D-optimaler Versuchsplan erstellt. Die Versuchsdurchführung erfolgte auf einem in eine Technikumsanlage eingebundenen Foulard mit horizontaler Walzenanordnung. Für jede der sieben Zielgrößen wurde auf Grundlage der erhaltenen Messwerte eine lineare Regressionsanalyse erstellt und ausgewertet. Eine detaillierte Analyse und Diskussion der Regressionsmodelle liefert Informationen zu Wirkungsrichtung und Intensität der einzelnen Einflussgrößen sowie zu Faktor-Faktor-Wechselwirkungen. / The subject of the work presented here is the study of the padding process for the chemical wet finishing of nonwovens at web speeds up to 250 m/min. Background to the topic is the repellent treatment of polypropylene spunbond nonwovens applied for surgical gowns. Finishing carried out at subcontractors corresponding to best practice technology up to now, the trend in the nonwovens industry is turning towards an in-house process mastery. Essential requirement to make the padding process technologically exploitable for this kind of application is the knowledge of the process characteristics at the high web speeds claimed. For the experimental scenario to be covered comprising six determining factors at three level steps each, a D-optimal trial plan was defined using the statistic method of the design of experiments (DOE). The realization of the trials carried out on a padder with horizontal roll arrangement installed in a pilot line. For each of the seven responses a linear regression analyses was compiled and evaluated. A detailed analysis and discussion of the regression models provides information on direction of influence as well as intensity of each of the determining factors and factor-factor-interactions.

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