Thesis (MScEng (Process Engineering))--University of Stellenbosch, 2010. / ENGLISH ABSTRACT: Distillation continues to be the most widely used method of separation in the processing industry, in spite of its inherently low thermodynamic efficiency. Two of the critical distillation research needs that arose from the US-Initiative Vision 2020 were to develop a better understanding of the physical phenomena as well as developing better predictive models. Also, characterisation of modern packing materials is required to assist in the CO2 capture optimisation. This thesis deals with both these aspects by establishing a facility that can accurately measure the hydraulic capacity of packed columns. This setup eliminates mass transfer and specific attention can be given to the hydrodynamic behaviour of packed columns. Two phenomena that have a large impact on the mass transfer efficiency of packing materials are the loading and flooding point. The loading point is signified by the following: a.) where the packed column hold-up increases, b.) higher increase in pressure drop, and c.) a decrease in Height Equivalent to a Theoretical Plate (HETP). The onset of flooding is where the shear forces between the gas and liquid become so large (relative to the gravitational forces) that a net upwards movement of liquid occurs, resulting in liquid droplets being heavily entrained. This is normally accompanied by a sharp increase in HETP, pressure drop and liquid hold-up. The prediction of these operating limits is of great value but, despite the many contributions that were made from 1960 to 2010, there is still room for improvement. The operating region of particular interest is between the loading and flooding point, especially for fluids with physical properties significantly different from that of water. In the past, this operating region was not of great importance, but industries are constantly striving to increase their production with minimal capital expenditure. Thus, packed columns are being pushed to their limits and a good understanding of the phenomena occurring near these operational limits is now required. A 400 mm diameter glass packed bed setup (with a bed height of 3000 mm) was designed and constructed to test the effect of the following parameters on packed bed pressure drop and liquid hold-up: · Gas and liquid physical properties · Gas and liquid rates · Type of packing (either random or structured) The experimental setup has been designed so that in the future the influences of the above mentioned parameters on entrainment can also be measured. Initially, hydrodynamic tests on random packing materials (1.5” Pall® Rings, 1.5” IMTP®, 1.5” Intalox® Ultra™) were conducted over a liquid range of 6 - 122 m3/(m2·h). Through a thorough literature study it was found that the most likely semi-theoretical model, that would be able to predict the pressure drop and the liquid hold-up over most of the random packing test range, was the model developed by Billet [1991; 1993; 1995; 1999]. The other models found throughout the literature had at least one of the following deficiencies: · Limited to only the pre-loading region. · Tested (and thus applicable) only over a very select group of packing materials with no attempt to generalise. · Lacked the proper validation of significantly variable fluid properties over multitudes of liquid and gas rates especially, at higher gas and liquid rates. The experimental setup was successfully commissioned, noting the following maximum experimental errors: Vapour flow factor - 2.6 %; liquid rate - 0.75 %; packed bed pressure drop - 0.75 %; liquid hold-up - 1.25 % and entrainment - 1.05 %. Significant deviations were observed between the experimental hold-up and the hold-up from the predictive model of Billet (using Pall® Rings). Careful inspection revealed that this predictive model potentially uses two definitions for hold-up at flooding, one which has a theoretical basis and the other purely empirical. Upon substituting the theoretical value with the empirical value, a significant improvement was observed between the measured and predicted results. Deviations were still observed near the flooding point and were attributed to the difficulty of obtaining reliable flooding data. The range of liquid hold-up prediction by Billet was only verified up to a liquid rate of 82 m3/(m2·h) and the pressure drop prediction only verified up to a liquid rate of 60 m3/(m2·h). This reinforces the need for high liquid, high gas rate data. Due to the empirical nature of the liquid hold-up at flooding prediction, and since pressure drop prediction is directly linked to liquid hold-up, another model was used to compare the experimental pressure drop data. The KG-TOWER® simulator was used to predict IMTP® data and compare it to the experimentally measured values. It was found that the experimental IMTP® data followed the same trends as those from KG-TOWER® within the operating limits of the program. Thus, since the experimental data follows similar trends as models found in the literature, as well as falling within their reliable limits, the experimental setup can correctly measure the parameters in question. The experimental data from the different random packings were compared to one another by using a statistical method to determine the loading point and onset of flooding. This method uses prediction confidence intervals by fitting empirical curves to each operating region and was found to be useful in determining these critical points from experimental hydraulic data (in the absence of HETP data).The only useful comparison was between IMTP® and Intalox® Ultra™ as they both have roughly the same density, size and void fraction. It was found that, on average, the pressure drop of Intalox® Ultra™ is 20 % lower than that of IMTP® over the entire operating range. The hydraulic operating range of Intalox® Ultra™ was found to be on average 16 % larger than that of IMTP®. It is recommended that further testing should be done to investigate the influence of fluid properties (specifically liquid viscosity and to a lesser extent surface tension) on the hydraulic capacity of packed columns. Also, high gas and high liquid rate data should be generated to assist current modelling techniques. Lastly, a comparative characterisation between Intalox® Ultra™ and Raschig Super-Rings would serve as a benchmark for fourth generation random packings. / AFRIKAANSE OPSOMMING: Distillasie is vandag nog die skeidingsproses wat die meeste gebruik word in the prosesnywerhede ten spyte van ‘n lae termodinamiese effektiwiteit. Twee van die kritieke distillasie navorsing behoeftes wat vanuit die US-Initiative Vision 2020 ontstaan het, was om die fisiese verskynsels beter te verstaan, asook om beter voorspellende modelle te ontwikkel. Die karakterisering van moderne pakking materiale is ook nodig vir die optimering van die verwydering van CO2 uit uitlaatstrome. Hierdie tesis spreek beide van hierdie faktore aan deur ‘n fasiliteit op te rig wat die hidrouliese kapasiteit van gepakte kolomme akkuraat kan meet. Hierdie opstelling elimineer massa-oordrag en dus kan spesifieke aandag gegee word aan die hidrodinamiese gedrag van gepakte kolomme. Twee verskynsels wat ‘n groot impak het op die massaoordrag effektiwiteit van pakkingsmateriale is die ladingspunt en die vloedpunt. Die ladingspunt word deur die volgende gekenmerk: a.) waar die vloeistof inhoud in die gepakte bed toeneem, b.) ‘n toename in drukval en c.) ‘n afname in die hoogte ekwivalent aan ‘n teoretiese plaat (HETP). Die vloed gebied word gekenmerk waar die skuifkragte tussen die vloeistof en gas so groot raak (relatief tot die gravitasionele kragte), dat daar ‘n netto opwaartse beweging van vloeistof druppels in die kolom is. Hierdie gaan normaalweg gepaard met ‘n skerp toename in HETP, drukval en vloeistof inhoud. Die voorspelling van hierdie bedryfslimiete is baie waardevol, maar ten spyte van die bydrae wat tussen 1960 en 2010 gemaak was, is daar nog steeds ruimte vir verbetering. Die spesifieke bedryfsgebied van belang is die gebied tussen die ladingspunt en die vloedpunt en spesifiek vir sisteme waar die fisiese eienskappe van die vloeistowwe drasties verskil van die van water. In die verlede was hierdie gebied van minder belang gewees, maar maatskappye probeer deesdae hul produksie opstoot met minimale kapitale uitleg. Dus is ‘n goeie kennis van massa-oordrag verskynsels naby aan die bedryfslimiete van kardinale belang. ‘n 400 mm Diameter gepakte kolom (met ‘n bed hoogte van 3000 mm en bestaande uit glas) opstelling is ontwerp en gebou om die effek van die volgende parameters te toets op gepakte bed drukval en vloeistof inhoud: · Gas en vloeistof fisiese eienskappe · Gas vloeistof vloeitempos · Tipe pakking (beide ongeordend en gestruktureerd) Die eksperimentele opstelling is ontwerp om die bogenoemde eienskappe op vloeistofmeesleuring te meet vir toekomstige navorsing. Hidrodinamiese toetse op ongeordende pakkingsmateriale (1.5” Pall® Ringe, 1.5” IMTP®, 1.5” Intalox® Ultra™) is uitgevoer vir vloeistof vloeitempos tussen 6 en 122 m3/(m2·h). Vanuit ‘n deeglike literatuurstudie is daar gevind dat die mees toepaslike semi-teoretiese model, wat die drukval sowel as die vloeistof inhoud kan voorspel oor al die bedryfsgebiede, is die model wat deur Billet [1991; 1993; 1995; 1999] ontwikkel is. Die ander modelle in die literatuur het ten minste een van die volgende tekortkominge gehad: · Is slegs van toepassing in die voor-ladings gebied. · Is slegs van toepassing vir ‘n paar pakkingsmateriale en geen poging is aangewend om dit te veralgemeen nie. · Is nie geldig waar die vloeistof eienskappe drasties verskil van ‘n lug/water sisteem nie, sowel as by hoë gas en vloeistof vloeitempos. Die eksperimentele opstelling is suksesvol in werking gestel met die volgende waargenome eksperimentele foute: Gas vloei faktor – 2.6 %; vloeistof vloeitempo – 0.75 %; gepakte bed drukval – 0.75 %; vloeistof inhoud – 1.25 %; vloeistof-meesleuring tempo – 1.05 %. Noemenswaardige verskille is waargeneem tussen die eksperimentele en teoretiese vloeistof inhoud (deur Pall® Ringe te gebruik). Na gelang van noukeurige inspeksie, is daar gevind dat die Billet-model twee moontlike definisies voorstel vir die voorspelling van vloeistofinhoud by die vloedpunt. Een van hierdie is teoreties van aard en die ander een suiwer empiries. ‘n Vervanging van die teoretiese waardes met die empiriese waardes het gelei tot ‘n merkwaardige verbetering tussen die eksperimentele en teoretiese voorspellings. Daar was nog steeds verskille naby aan die vloedpunt, maar dit kon toegeskryf word aan die feit dat min betroubare data naby aan die vloedpunt beskikbaar is. Die voorspelling van vloeistof inhoud deur Billet is slegs gekontroleer tot ‘n vloeistof vloeitempo van 82 m3/(m2·h) en die drukval slegs tot ‘n vloeistof vloeitempo van 60 m3/(m2·h). Die bogenoemde bewys dus die tekort aan hoë gas- en hoë vloeistofvloeitempo data. Die voorspellende model se drukval is gekoppel aan die vloeistof inhoud, en dus is ‘n ander model gebruik om die eksperimentele drukval data teen te vergelyk. Die KG-TOWER® simulasie program is gebruik om die IMTP® drukval te voorspel en dit het goed vergelyk met die eksperimentele data. Dus, aangesien die eksperimentele data dieselfde tendens toon as dié van die modelle in die literatuur en aangesien dit binne die modelle se foutbande val, kan die eksperimentele opstelling die verlangde parameters akkuraat meet. Die eksperimentele data van al drie pakkingsmateriale is teenoor mekaar vergelyk deur gebruik te maak van ‘n statistiese metode wat die ladings- en vloedpunt bepaal. Hierdie metode maak gebruik van voorspellings vertroue intervalle deur empiriese kurwes op die eksperimentele data in elke bedryfsgebied te pas. Hierdie metode is ontwikkel om toepaslike te wees in die afwesigheid van HETP data. Die enigste nuttige vergelyking is tussen IMTP® en Intalox® Ultra™ omdat albei dieselfde pakkingsdigtheid, grootte en pakkings oop ruimte het. Daar is gevind dat die drukval van Intalox® Ultra™ ‘n gemiddeld van 20 % laer is as dié van IMTP® oor die hele bedryfsgebied. Die hidrouliese bedryfsgebied van Intalox® Ultra™ is 16 % groter as dié van IMTP®. Daar word voorgestel dat bykomende toetswerk gedoen moet word om die invloed van vloeistof eienskappe (spesifiek vloeistof viskositeit en vloeistof oppervlak spanning) op die hidrouliese kapasiteit van gepakte kolomme te ondersoek. Bykomende toestwerk by hoë gas- en hoë vloeistofvloeitempo word benodig om die bestaande modelle aan te vul. Laastens, sal ‘n vergelykende studie tussen Intalox® Ultra™ en Raschig Super-Rings die grondslag lewer vir die karakterisering van vierde generasie ongeordende pakkingsmateriale.

In this dissertation I focus on two considerations that influence the product strategy of a firm. The first is consumers’ choice and its influence on a firm’s product offering, and the second is the interaction between durable products and their contingent consumables. First, I study the assortment planning problem for a firm; I illustrate the complexity of solving this product selection problem, present simple solutions for some commonly used choice models, and develop heuristics for other practically motivated models. Second, I study the incentives of a durable goods monopolist when she can lock-in consumers through a contingent consumable. Adopting a lock-in strategy has two interesting effects on the incentives of a durable goods manufacturer. On one hand, by locking-in consumers to its consumable, a durable goods monopolist can curb its temptation to reduce durable prices over time, thereby mitigating the classic time inconsistency problem. On the other hand, lock-in will create a hold-up issue and adversely affect consumers’ expectations of future prices for the consumable. My research demonstrates the trade-off between time inconsistency and hold-up, and derives insights about the conditions under which a lock-in strategy can be effective. I further analyze the trade-off between time inconsistency and hold-up associated with lock-in in the presence of consumable stock-piling. My findings indicate in the presence of consumer stock-piling, lock-in has an effect similar to that of competition in the consumables market: they help to dampen the hold-up problem that arises from lock-in and at the same time increase the manufacturer’s incentive to reduce durable prices over time. / text

Univ., Diss.--Kiel, 2003.

Abstract : The industrial partner of this project uses a slurry bubble reactor for the production of biogenic methanol. In the latter syngas is dispersed into the slurry continuous phase containing both liquid and solid phases. The rising bubbles containing a wide spectrum of the bubbles sizes, interact with the continuous phase due to the interface momentum transfer. The latter includes the drag, lift, wall lubrication and turbulent dispersion terms that require average bubble size, which needs to be calculated. One way to predict this average bubble size is by using population balance model (PBM), which can be coupled with the Eulerian framework. PBM also needs closure kernels for the bubble coalescence and bubble breakup. In this study, the influence of bubble coalescence and bubble breakup kernels have been studied in two- and three-phase system using eulerian approach, which solves momentum equation for each phase. The influence of the mesh sizes, number of bubble classes, numerical schemes, wall lubrication force and turbulent dispersion force are also included. In the two-phase system, results show that the Luo coalescence model needs to be tuned when used in combination with the Luo breakup kernel. The combination of the Luo coalescence and the Lehr breakup kernels (Luo-Lehr) show promising time-averaged radial profiles of gas holdup and axial liquid velocity as compared to empirical values. In the three-phase system, the combination of the Luo coalescence and the Lehr breakup kernels (Luo-Lehr) and the Luo coalescence and the Luo breakup kernels (Luo-Luo) predict convincing time-averaged radial profile of axial solid velocity as compared to experiments. However, at an elevated superficial gas velocity, a non-realistic behavior was predicted when compared to empirical observations. The sensitivity analysis results show that the 3 mm mesh size depicts a trend similar to the empirical values of the radial profiles of the gas holdup, axial liquid velocity, and solid axial velocity. The number of bubble classes influence the predicted bubble size distribution in the three-phase system while the numerical discretizing schemes have no influence on the results. The bench simulation results show that the inclusion of the turbulent dispersion term using a single porous tubular sparger influences the hydrodynamic behavior of the bubble column. / Le partenaire industriel de ce projet utilise un réacteur à suspension à trois phases pour la production de méthanol biogénique. Dans celui-ci, le gaz de synthèse est diffusé par barbotement dans la phase à suspension qui contient à la fois les phases liquide et solide. Les bulles en ascension présentent un large spectre de tailles et interagissent avec la phase à suspension en échangeant de la quantité de mouvement via leurs surfaces. Cet échange comprend les forces de trainé, de portance, de lubrification en proche parois et de dispersion par turbulence; lesquelles requièrent notamment le calcul de la taille moyenne des bulles. Une façon de prédire numériquement cette taille moyenne est de recourir à un modèle de bilan de population (PBM, de l’anglais Population Balance Model), qui peut être couplé avec un model multiphasique eulérien. Un tel PBM a requière des modèles de fermetures pour la coalescence et la rupture des bulles. Dans la présente étude, l'influence des modèles noyaux de coalescence et de rupture des bulles a été étudiée pour des systèmes à deux et à trois phases en utilisant l’approche eulérienne. L'influence de la taille du maillage, du nombre de classes de bulles, du schéma numérique, de la force de lubrification en proche parois et de la force de dispersion par turbulence sont également incluses. Dans un système bi-phasique, les résultats montrent que le modèle de coalescence Luo doit être ajusté lorsqu'il est utilisé en combinaison avec le noyau de rupture Luo. La combinaison des noyaux de coalescence Luo et de rupture Lehr (Luo-Lehr) montrent des profils radiaux moyennés dans le temps qui sont valides pour la concentration de gaz et la vitesse axiale du liquide par rapport aux mesures expérimentales. Dans le système triphasé, la combinaison des modèles noyaux de coalescence de Luo et de rupture de Lehr (Luo-Lehr) et de la coalescence de Luo et de rupture de Luo (Luo-Luo) prédisent des profils radiaux moyennés dans le temps qui sont valides pour la vitesse axiale moyenné dans le temps par rapport aux expériences. Cependant, à une vitesse de gaz superficielle élevée, ces profils prédisent un comportement non réaliste par rapport aux observations empiriques. Les résultats de l'analyse de sensibilité du maillage montrent qu’avec des cellules de 3 mm, le model prédit une tendance similaire aux valeurs empiriques pour les profils radiaux de concentration du gaz, de vitesse axiale du liquide et de vitesse axiale solide. Le nombre de classes de bulles influe sur les distributions prédites de taille de bulle dans le système triphasé alors que les schémas de discrétisation numériques n'ont aucune influence sur les résultats. Les résultats des simulations d’un banc d’essai avec diffuseur à bulles poreux montrent que tenir compte du terme de dispersion influence le comportement hydrodynamique de la colonne à bulles.

Diese Arbeit besteht aus drei zusammengehörigen Essays, die eine theoretische Grundlage für Untersuchungen multilateraler Verhandlungen und strategischer Investitionen in drei unterschiedlichen Umgebungen liefert. Die vorgestellten Methoden werden angewandt um Entwicklungen in der eurasischen Gasversorgung zu analysieren. Der erste analytische Teil befasst sich mit multilateralen Verhandlungen zwischen Russland und den Transitstaaten für sein Gas, namentlich: Ukraine, Weißrussland und Polen. Es wird angenommen dass die beteiligten Länder heterogen sind und dass einige von ihnen nicht die Fähigkeit besitzen langfristige Zusagen zu machen. Wir wenden ein zweistufiges spieltheoretisches Konzept an um Verzerrungen in Investitionen in das Pipeline System, welches russisches Gas nach Westeuropa transportiert, zu analysieren. Unsere qualitative und quantitative Analyse liefert eine strategische Begründung für den Überschuss an gebauten Kapazitäten und erklärt Überinvestitionen in einige Teilstrecken und Unterinvestitionen in andere als ein Versuch ein Kräftegleichgewicht zu erzeugen. Der zweite Teil beschäftigt sich mit multilateralen Verhandlungen und der Etablierung von Bündnissen in der Gegenwart von externen Effekten. Wir untersuchen ob das Szenario zweier konkurrierender Versorgungsketten, nämlich der russischen und der kaspischen, wahrscheinlich ist oder ob sich eher ein Monopol in der Versorgung herausbildet. Im Besonderen gehen wir auf die Fragestellung ein, wie die Verhandlungsmacht der Beteiligten in diesem Netzwerk von der Struktur des bestehenden Netzwerks und seiner möglichen Änderungen abhängt. Wir zeigen auf, warum die Spieler im Gleichgewicht eine große Koalition bilden. Die dritte Studie richtet sich auf die Formation von Koalitionen in einem Umfeld mit verzögerten externen Effekten. Indem wir ein zweistufiges Spiel benutzen, untersuchen wir, wie die Unfähigkeit der Spieler zu einem langfristigen geteilten Gewinn beizutragen zu strategischen Verzerrungen in Investitionen führen kann. Wir finden heraus, dass Unter- und Überinvestitionen in der Zukunft wahrscheinlich sind, wenn die Spieler nicht in der Lage sein werden langfristige Beziehungen miteinander einzugehen. / This thesis consists of three related essays, which develop the framework to study multilateral bargaining and strategic investments under three different environments. The introduced novel methodologies are applied to analyze developments in the Eurasian gas supply chain. The first analytical part of the thesis concerns multilateral bargaining Russia and transiters for its gas, Ukraine, Belarus, and Poland. The players are assumed to be heterogeneous, some lacking the ability to make long--term commitments. We apply a two stage game to analyze distortions of investments into the pipeline system supplying Russian natural gas to Western Europe. Our qualitative and quantitative analysis provides a strategic rational behind excess capacities, which were built, and explains overinvestment on some tracks and underinvestment on others as an attempt to create countervailing power. The second part of the thesis deals with multilateral bargaining and coalition formation issues in the presence of externalities. We study whether two competing supply chains, Russian vs. Caspian, are likely to be formed or monopoly supply will be organized. We quantify the strategic value of different investment options. In particular, we examine how the bargaining power of the network players depends on the architecture of the existing network and its possible extensions. We show why the players form a grand coalition in equilibrium. The third study focuses on coalition formation and bargaining in the environment with externalities under the hold-up. Using a two stage game we study how the inability of players to commit to long-term profit sharing may lead to strategic distortions in investments. We find that underinvestment and overinvestment are likely to happen in the future, if the players will not be able to build stable long-term relation. The main contribution of the work is in developing a new methodology to study multilateral bargaining and strategic investment problems and in confronting the theory with the real world experience.

The Canadian canola breeding sector met a transition from publicly funded breeding research to large private investments in research and development (R&D). The increasing use of biotechnology tools in the mid 1990s made the assignment of plant ownership technically possible while the legislative safeguards that were put in place during the same period enabled owners to take juristic actions against potential infringers. Today, canola breeding sector is dominated by large multinational firms. The generation of proprietary knowledge in the canola breeding sector has caused a freedom to operate issue. Private and public firms conducting canola R&D are seriously concerned about their ability to gain and preserve access to key technologies in an IPR world. <p>This thesis uses the tragedy of the anticommons framework to analyze the consequences of increased intellectual property protection in the canola breeding sector. Theory suggests that when a common resource is owned by multiple owners, each of the owners has the incentive to overcharge potential users, leading to the underuse of the resource. In R&D, different owners of complementary technologies may overcharge potential R&D firms that want to assemble different technological pieces to produce a new one. The result is forgoing research and development of new products.<p>The results of personal interviews with thirteen canola researchers and IP officers are presented and analyzed. The results suggest that the increase in the intellectual property protection in the last two decades in the canola breeding sector has led to difficulties with canola R&D. These difficulties take the form of reduced access to current, proprietary and public material. With hampered access to research input material, research output is not maximized and potential research may be forgone. Interviewees described how the increase in the intellectual property protection affects their personal and organizations ability to conduct research as well as some the implications of the new IP regime on the canola breeding sector. There is indication that canola breeding sector is moving towards a super-protectionism. Under these conditions, canola R&D firms, private and public, are in search for ways that will open access to enabling technologies and research areas. The creation of platform technologies and collaborations are the most prominent ones and are observed to increase in occurrence world wide.

The Canadian canola breeding sector met a transition from publicly funded breeding research to large private investments in research and development (R&D). The increasing use of biotechnology tools in the mid 1990s made the assignment of plant ownership technically possible while the legislative safeguards that were put in place during the same period enabled owners to take juristic actions against potential infringers. Today, canola breeding sector is dominated by large multinational firms. The generation of proprietary knowledge in the canola breeding sector has caused a freedom to operate issue. Private and public firms conducting canola R&D are seriously concerned about their ability to gain and preserve access to key technologies in an IPR world. <p>This thesis uses the tragedy of the anticommons framework to analyze the consequences of increased intellectual property protection in the canola breeding sector. Theory suggests that when a common resource is owned by multiple owners, each of the owners has the incentive to overcharge potential users, leading to the underuse of the resource. In R&D, different owners of complementary technologies may overcharge potential R&D firms that want to assemble different technological pieces to produce a new one. The result is forgoing research and development of new products.<p>The results of personal interviews with thirteen canola researchers and IP officers are presented and analyzed. The results suggest that the increase in the intellectual property protection in the last two decades in the canola breeding sector has led to difficulties with canola R&D. These difficulties take the form of reduced access to current, proprietary and public material. With hampered access to research input material, research output is not maximized and potential research may be forgone. Interviewees described how the increase in the intellectual property protection affects their personal and organizations ability to conduct research as well as some the implications of the new IP regime on the canola breeding sector. There is indication that canola breeding sector is moving towards a super-protectionism. Under these conditions, canola R&D firms, private and public, are in search for ways that will open access to enabling technologies and research areas. The creation of platform technologies and collaborations are the most prominent ones and are observed to increase in occurrence world wide.

Universiẗat, Diss.--Köln, 2003.

Made available in DSpace on 2016-04-28T20:37:40Z (GMT). No. of bitstreams: 1 Ida Elizabeth Cardinalli.pdf: 513996 bytes, checksum: a5f906486c5d7f5388fcc1082ebd9492 (MD5) Previous issue date: 2011-07-06 / Urban violence is currently a complex and worrying issue so much so that national and international organizations have been calling for studies in its various aspects. This research was developed with a focus on the impact of urban violence on the health and illness of its victims, based on an overriding concern: explaining and clarifying the meaning and significance of the experience of those who suffered urban violence, such as hold-up and/or express kidnapping. The methodology was based on the existential-phenomenological thinking, in particular Martin Heidegger s, who understands human existence as being-there and being-in-the-world, seeking to understand the experience of victims of urban violence in its entirety. The methods used included interviews with three participants and focal psychotherapy with one with 23 sessions of 50 minutes each. The participants were two men and one woman, all married, and aged between 48 to 53 years. The analysis of the results was organized along two axes: thematic and temporal. The results suggest that the victims of hold-up or express kidnapping show significant distress, when the experience of violence remains trapped in the sense of risk, threat and danger. The impact of violence can also affect the understanding of oneself, of others and the world with the sudden approach of the dimensions of unpredictability, precariousness and vulnerability resulting from a situation of violence. The discussion of the results is extended to possible applications in the Public Health Service. Topics for future research that articulate Clinical Psychology and urban violence are also listed. (Supported by CEPE/PUC-SP) / A violência urbana é uma problemática complexa e preocupante na atualidade, tanto que os organismos internacionais e nacionais têm solicitado estudos da suas diversas facetas. O desenvolvimento da presente pesquisa focalizou o impacto da violência urbana na saúde e adoecimento em suas vítimas, pautado pela questão norteadora: explicitar e esclarecer o sentido e os significados da experiência de quem sofreu violência urbana como assalto e/ou sequestros relâmpago ou de curta duração. A metodologia foi baseada no pensamento fenomenológico-existencial, em particular, de Martin Heidegger, que entende o existir humano como ser-aí e ser-nomundo, buscando compreender a experiência da vítima de violência urbana em sua totalidade. Os métodos utilizados foram entrevistas de três participantes e a psicoterapia focal de um deles, com 23 sessões de 50 minutos cada uma. Os participantes foram dois homens e uma mulher, todos casados, entre 48 a 53 anos. A análise dos resultados foi organizada em dois eixos: temáticos e temporais. Os resultados sugerem que as vítimas de assalto e sequestros relâmpago ou de curta duração mostram sofrimento significativo, quando a experiência de violência permanece aprisionada no sentido de risco, ameaça e perigo. O impacto da violência pode abalar, ainda, a compreensão de si mesmo, do outro e do mundo com a aproximação abrupta das dimensões de imprevisibilidade, precariedade e vulnerabilidade abertas pela situação de violência. A discussão dos resultados é ampliada para possíveis aplicações no Serviço Público de Saúde. São indicados também temas para futuras pesquisas que articulem a Psicologia Clínica e a violência urbana. (Apoio CEPE/PUC-SP)

Este estudo faz uma análise teórica e empírica dos processos de licitação e contratação de obras e reformas de prédios públicos em uma Universidade Pública Federal, utilizando a Teoria da Informação Assimétrica e dos Contratos. O período da pesquisa foi entre 2010 a 2013, na Universidade Federal do Rio Grande do Sul, sendo que foram analisados 127 processos licitatórios e contratos. As análises revelaram diversas ocorrências em licitações e nas contratações de obras e reformas. Na etapa licitatória, anterior à contratação (ex ante), a sessão para lances das licitações de obras e reformas, em alguns casos, estiveram desertas. Na contratação e execução de obras e reformas (ex post), foram constatados diversos pedidos de prorrogação de prazos e de reequilíbrio econômico financeiro, e na fiscalização das obras e reformas foram constatadas 31 ocorrências nos serviços finalizados pelas Empreiteiras. Os resultados também indicaram que, do total dos processos analisados no período de 2010 – 2013, cerca de 30% das obras e reformas ainda não foram finalizadas ou estão suspensas, o que demonstra deficiências na fiscalização e na gestão dos contratos. Além disso, o tempo médio entre a abertura do processo e a conclusão dos serviços gira em torno de três anos, sendo que grande parte deste tempo foi despendido com procedimentos internos da UFRGS. Tais fatos indicam problemas de seleção adversa e assimetria de informações, além do Hold up problem, em que o Principal é tomado como refém pelo Agente e do problema do Risco moral (Moral Hazard), em que o Agente passa a agir de modo não apropriado ou não aprovado pelo Principal, com a ocorrência dos custos de transação. / This study makes a theoretical and empirical analysis of the processes of bidding and contracting works and reforms of public buildings in a Federal Public University, using Asymmetric Information Theory and Contracts. The period analyzed was between 2010 and 2013, at the Federal University of Rio Grande do Sul, being that 127 bidding processes and contracts were analyzed. The analyses revealed several occurrences in tenders and hiring of work and restoration. In the bidding phase, prior to hiring (ex ante), the bidding session for work and renovations, in some cases, was deserted. There were several requests for deadline extension, and economic-financial adjustment in the work and restoration hiring and execution (ex post), while in the inspection of work and restoration it could be noticed 31 occurrences in services finalized by the contractors. The results also indicated that, of the total number of processes analyzed in the period 2010-2013, about 30% either have not been completed or are suspended, which shows deficiencies in the supervision and management of the contracts. In addition, the average time between the opening of the process and the conclusion of services is about three years, and much of this time was spent with internal procedures of UFRGS. These facts indicate problems of adverse selection and information asymmetry , in addition to the "Hold up problem", in which the Principal is taken hostage by the Agent besides the problem of Moral Hazard, when the Agent begins to act inappropriately or in a way which is disapproved by the Principal, together with the incidence of transaction costs.