Rock masses may present remarked geostatic stress anisotropy and anisotropic material properties; thus, the tunnel alignment with the geostatic principal stress directions and with the axes of material anisotropy is unlikely. Nevertheless, tunnel design often neglects those misalignments and; yet, the misalignment effects were unknown. In this doctoral research, tunnels under complex anisotropic conditions were modelled analytically and numerically with 3D nonlinear Finite Element Method (FEM). When the tunnel misaligns with the geostatic principal stress directions, anti-symmetric axial displacements and shear stresses are induced around the tunnel. Analytical solutions for misaligned shallow and deep tunnels in isotropic elastic ground are provided. The analytical solutions were validated with 3D FEM analyses. Near the face, the anti-symmetric axial displacements are partially constrained by the tunnel face, producing asymmetric radial displacements and stresses. The asymmetric radial displacements at the face can be divided into a rigid body displacement of the tunnel cross-section and anti-symmetric radial displacements. Those asymmetries may affect the rock-support interaction and the plastic zone developed around the tunnel. In anisotropic rock masses, the tunnel misalignment with the axes of material anisotropy also produces anti-symmetric axial displacements and stresses around the tunnel. It occurs because when the tunnel is not aligned with the principal material directions, the in-plane stresses are coupled with the axial displacements (i.e. the compliance matrix is fully populated). Thus, tunnels in anisotropic rock mass not aligned with the geostatic principal stresses and with the axes of material anisotropy are substantially more complex than tunnels not aligned with the principal stress directions in isotropic rock mass. An analytical solution for misaligned tunnels in anisotropic rock mass is provided. It was observed that the relative orientation of the geostatic principal stresses with respect to the axes of material anisotropy plays an important role. The axial displacements produced by far-field axial shear stresses and by the rock mass anisotropy may compensate each other; thus, axial and radial displacements around the tunnel are reduced. On the other hand, those anti-symmetric axial displacements may be amplified; thus, the ground deformations are increased. Asymmetric radial and axial deformations, and asymmetric spalling of the tunnel walls are commonly observed on tunnels in anisotropic rock masses. The tunnel misalignment with the geostatic principal stress directions and with the axes of material anisotropy could be associated with those phenomena that, so far, are not well comprehended

The question of an equilibrium exchange rate has always been a debatable issue. Along with rapid growth of the Chinese economy over the past two decades, a number of studies have been undertaken to investigate whether or not the RMB exchange rate is at its long run ‘equilibrium’ level. Because the equilibrium exchange rate affects the competitiveness of a country’s economy, these studies have focused on whether or not the real exchange rate is misaligned with respect to its long-run equilibrium level. One of the main reasons for this concern is that effective management of the exchange rate system could help a country’s economy achieve internal and external balance. Otherwise, it could negatively influence the stability of a country’s financial economy, possibly resulting in regional financial crises. This study estimates time varying values of the equilibrium real effective exchange rate (EREER) and associated exchange rate misalignments for China in recent years (from the first quarter of 1999 to fourth quarter of 2007). The study focuses on the reduced-form equilibrium real exchange rate (ERER) model for developing countries presented by Elbadawi (1994) and follows Edwards’ (1989, 1994) work on models of exchange rate determination. We identify the terms of trade, openness, government expenditure, productivity, and money supply as important explanatory variables of the RMB long-run equilibrium value. We use the Johansen-Juselius (1990) co-integration procedure to analyse our data. Using the ERER model, our results show there is a cointegrating relationship between the real effective exchange rate and its economic fundamentals. Subsequently, compare to other previous studies discussed in Chapter 2, our restricted error-correction model suggests that the extent of the misalignment is not very large, moving in a narrow band of plus and minus 12 percent of the long-run equilibrium level during the sample period. Focusing on the RMB real exchange rate misalignment in recent years, our result shows that the RMB was undervalued by an average of 6.7 percent during the period of 2005Q:3-2007Q:4. Furthermore, our short-run empirical error correction model indicates that, on average, the real exchange rate takes over one quarter to reach its long-run equilibrium level.

Current board technologies are inherently performance-limited (FR-4) or cost-prohibitive (Al2O3/AlN). Next-generation high-density packaging applications would necessitate a new base substrate material to achieve ultra-fine pitch solder-joint reliability and multiple layers of fine-line wiring at low cost. The NEMI 2000 roadmap defines the need for 4-8 layers of 5-10 m wiring for future system boards. The 2003 ITRS roadmap calls for organic substrates with less than 100-m area-array pitch in the package or board by year 2010. Solder-joint reliability at such fine-pitch is a matter of concern for the industry. Use of underfills reduces thermal stresses but increases cost and, in addition, their dispensing becomes increasingly more complicated with the shorter gaps required for future interconnects. Therefore, there is a pronounced need to evaluate board materials with CTE close to that of Si for reliable flip-chip on board without underfill. Recently, a novel manufacturing process (using polymeric precursor) has been demonstrated to yield boards that have the advantages of organic boards in terms of large-area processability and machinability at potentially low-cost while retaining the high stiffness (~250 GPa) and Si-matched CTE (~2.5 ppm/㩠of ceramics. This work reports the evaluation of novel SiC-based ceramic composite board material for ultra-fine pitch solder-joint reliability without underfill and multilayer support. FE models were generated to model the behavior of flip-chips assembled without underfill and subjected to accelerated thermal cycling. These models were used to calculate solder-joint strains which have a strong direct influence on fatigue life of the solder. Multilayer structures were also simulated for thermal shock testing so as to assess via strains for microvia reliability. Via-pad misregistration was derived from the models and compared for different boards. Experiments were done to assemble flip-chips on boards without underfill followed by thermal shock testing so as to get the number of cycles to failure. To assess microvia reliability, 2 layer structures containing vias of different diameters were fabricated and subjected to thermal cycling. Via-pad misalignment was also studied experimentally. Modeling and experimental results were corroborated so as to evaluate thermomechanical suitability of C-SiC for high-density packaging requirements.

Submitted by Lucienne Costa (lucienneferreira@ufcg.edu.br) on 2018-04-12T17:33:48Z No. of bitstreams: 1 PAULO VICTOR DA SILVA OLINDA – DISSERTAÇÃO (PPGEM) 2018.pdf: 4406932 bytes, checksum: 3015875e87b33898358c6dc22f3c9e3a (MD5) / Made available in DSpace on 2018-04-12T17:33:48Z (GMT). No. of bitstreams: 1 PAULO VICTOR DA SILVA OLINDA – DISSERTAÇÃO (PPGEM) 2018.pdf: 4406932 bytes, checksum: 3015875e87b33898358c6dc22f3c9e3a (MD5) Previous issue date: 2018-02-21 / Capes / O objetivo deste trabalho foi realizar um estudo termográfico visando constatar falha de montagem por desalinhamento em acoplamento flexível do tipo garra, modelo GR 50. A metodologia da pesquisa pode ser caracterizada como do tipo aplicada, quantitativa, explicativa, bibliográfica e experimental. Para tanto, montou-se uma bancada experimental contendo um motor trifásico, eixos, rolamentos e o acoplamento flexível, sem a presença de cargas, destinado a solidarizar dois eixos contendo desalinhamentos entre eles de 0,5; 0,74 e 1,18 mm. Como resultado dos testes efetuados, foi possível perceber que a temperatura do acoplamento aumenta à mesma proporção dos desalinhamentos inseridos, ou seja, quanto maior o desalinhamento, maior a temperatura registrada. Este fato é melhor observado nos primeiros 20 minutos dos testes. Diante destes resultados é possível afirmar que a Termografia pode ser utilizada como técnica de detecção de falhas de montagem por desalinhamento nos primeiros minutos de funcionamento do sistema. / The aim of this work is to perform a thermographic study aiming to verify assembly failure by mounting in flexible claw type coupling, model GR 50. A research methodology can be characterized as applied, quantitative, explanatory, bibliographic and experimental type. For this, an experimental bench was built, containing a three-phase motor, shafts, bearings and the flexible coupling, without a load presence, to join two shafts with misalignments between them; 0.5, 0.74 and 1.18 mm. As a result of the tests performed, it was possible to notice that the temperature of the coupling increases the same proportion of the misalignments inserted, that is, the greater the misalignment, the higher the temperature recorded. This fact is best observed in the first 20 minutes of the tests. In view of these results, it is possible to affirm that the thermography can be used as a technique for detecting mounting faults by misalignment in the first minutes of the system operation.

L’objet de cette thèse est l’analyse des effets de la variabilité du taux de change réel effectif (TCRE) sur le commerce extérieur de la Tunisie global et sectoriel sur la période de 1975-2009. La variabilité du TCRE signifie la volatilité et le mésalignement. La volatilité est mesurée par l’écart type mobile (ETM) et le modèle GARCH(1,1). Cependant le mésalignement du TCRE est mesurée par la déviation par rapport aux taux d’équilibre donnés par trois théories du taux de change d’équilibre à savoir le modèle d’Edwards, de BEER et du NATREX. A l’aide des estimations des modèles d’exportations et d’importations sans/avec ruptures, les résultats ont montré que les effets de la volatilité sur le commerce extérieur ne sont pas très pertinents à long terme. Quant aux effets du mésalignement du taux de change, ceux-ci apparaissent très pertinents essentiellement lorsque il s’agit des flux commerciaux sectoriels. / The purpose of this thesis is the analysis of the variability of the real effective exchange rate (REER) on foreign trade total and sectoral of Tunisia over the period 1975-2009. Variability REER means volatility and misalignment. Volatility is measured by the mobile standard deviation (ETM) and the GARCH (1, 1). However, the misalignment of REER is measured by the deviation from the equilibrium rate given by three theories of exchange rate equilibrium namely the Edwards model, BEER and NATREX. Using estimates of exports and imports models with / without breaks, the results showed that the effects of volatility on trade are not very relevant in the long term. But the effects of the exchange rate misalignment appear very relevant mainly when the sectoral trade flows are used.

This thesis seeks to contribute to decision support for policy makers in the transport sector. In order to frame the papers and to relate them to the broad field of “policy analysis”, I have structured the papers around a simple framework with three decision levels: responsibility, policy gap, and policy measure. The thesis contains five papers. “Transaction and transition costs during the deregulation of the Swedish Railway market” is a paper in the transaction cost school. We studied the costs associated with the shift from monopoly to competition in the Swedish railway market, and we found that the change resulted in comparatively small transaction costs, but that transition and misalignment costs seem to be larger.  In “Parking policy under strategic interaction”, I examined the effect of strategic interaction between jurisdictions using an analytical model based on Hotelling’s linear city model. I conclude that the procedure for setting supply in most municipalities has a strong downward effect on municipal parking fees and that resource flow competition implies that the fees are higher than the efficient prices (but that the effect of the supply procedures makes this effect incongruous). In “Validation of aggregate reference forecasts for passenger transport”, we followed up the Swedish national forecasts for passenger transport produced from 1975 to 2009 and tried to explain the deviations. We found that the forecasts during the last decades have overestimated car traffic, and that this is due to input errors. The potential problem of using cross-sectional models for forecasting intertemporal changes seems to have been limited. In “The kilometer tax and Swedish industry - effects on sectors and regions”, we estimated factor demand elasticities in the Swedish manufacturing industry and used these to analyze the effects of a kilometer tax for heavy goods vehicles. We found that the kilometer tax leads to factor substitution in that it decreases transport demand and increases labor demand. The effects on output are less pronounced.   In “The effect of minimum parking requirements on the housing stock”, we used a model of the rental, asset, and construction markets. We quality-assured our assumptions and our results through interviews with market actors. In our example suburb, we found that parking norms reduced the housing stock by 1.2% and increased rents by 2.4%. / <p>QC 20171026</p>

MedTech firms experience barriers when entering the healthcare sector, although their solutions could solve healthcare challenges. The study provides a conceptual framework for MedTech firms' business environment including institutional alignments and misalignments. These insights support MedTech firms' business model development when aiming for successful commercialization. The research is conducted with a multiple case study analyzing MedTech firms' and healthcare organizations' perspective regarding the business environment and relationship dynamics. The study generated three main findings. Firstly, an organizational and institutional logic analysis outlined essential problem areas where MedTech firms and healthcare organizations align differently. Secondly, suggestions on how the MedTech firm can respond to the identified problem areas through their business model are presented. Thirdly, the study provides an example of how social- and business literature can be connected to understand complex business environments. In contrast to a majority of prior research, the study is designed for the MedTech firm's perspective where the final result answering how the business model can be improved based on healthcare organizational and business insights.

Magister Commercii - MCom / Issues pertaining to the misalignment of exchange rate have become central in the analysis of open economy macroeconomics for developing countries. This is at least due to two reasons: first persistent overvaluation of currency is seen as a powerful early warning of potential currency crisis and second protracted periods of exchange rate misalignment are highly associated with poor economic performance in a number of developing countries. Owing to this fact, economists are in concession that aligning real exchange rates towards their equilibrium values is an important component of macroeconomic policy adjustments in order to achieve and maintain a sustainable development. For this purpose the estimation of the degree of the real exchange rate misalignment has become pivotal. However, despite the concession among economists regarding the need to minimize the frequency and magnitude of exchange rate misalignment, the estimation of the equilibrium exchange rate (hence the misalignment) has been among the most controversial and challenging issues in modem macroeconomics. For several decades, the Purchasing power parity (PPP) approach-which is based on the law of one price-has been the most widely used methodology for the estimation of the equilibrium exchange rate in both developed and developing countries. In South Africa some attempts have been made to estimate the misalignment of the rand against major currencies on the basis of the PPP approach. However, large numbers of empirical studies show that PPP does not hold except in the 'ultra' long run. In addition, PPP's assumption of a constant equilibrium exchange rate makes it ill-fitted to serve as a bench-mark for the analysis of the exchange rate in countries such as South Africa that experience substantial structural changes. As a result a number of macro-econometric models underlying on the macroeconomic determinants of exchange rate have been developed, albeit with little applicability in developing countries. In this study, we have used Edwards' (1989) intertemporal general equilibrium model of a small open economy in order to estimate the degree of the real exchange rate misalignment and its impact on the international trade competitiveness of the South African economy for the period 1985:1-2000:4. For this purpose a dynamic single equation error correction model of a first order autoregressive distributed lag model, ADL (1,1), and five years moving average technique have been employed to estimate the exchange rate misalignment. Whereas impulse response analysis and variance decomposition techniques of a cointegrated VAR (vector auto regression) have been established to assess the impact of the misalignment on trade competitiveness. The fmdings of the study reveal that the real exchange rate had been consistently overvalued during the period' 1988:3-1998:2 but undervalued during periods 1998:3- 2000:4. For most of the periods during 1985:1-1988:2 the rand had been undervalued. More over the study discloses that exchange rate misalignment debilitates South Africa's international trade competitiveness accounting for 20 percent of the variation in competitiveness.

Lean production and Lean philosophy have been developed, studied and implemented over the world since it was know from Toyota Production System. International manufacturers/OEMs have more or less developed their own Lean production systems. Over the years, arising challenges from new technology and internationalization have force the OEMs to understand and evaluate the design of supply chain to support their lean production system, and to manage the SC and compete as a whole against other supply chains. When apply Lean principles to the level of Supply Chain, coordination is an essential element to success. Today, researches have been done on joint efforts on decision making among supply chain actors, and applying Lean tools such as VSM on an extended level, namely a supply chain. Whereas the methods to improve SC coordination when implementing Lean through SC remain undeveloped. By interviewing Lean supply chain experts, experienced personnel in Supply Chain Management, and Lean experts from various organizations, a methodology to identify and visualize the improvement areas in supply chain coordination was designed. The methodology was then tested in a European OEM’s supply chain. Value Stream Mapping, as the base, was adapted to support identification and visualization of improvement areas in supply chain coordination. Several misalignments in the SC coordination were found in the current state, then visualized in current state map and approved by various SC actors. The methodology was then improved according to the process of testing. The purpose of this thesis is to develop a methodology to identify and visualize the improvement areas in (manufacturing) supply chain coordination within a Lean perspective.

The cone-beam flat panel micro-CT is a high definition imaging system. It acquires projections of an object or animal to reconstruct a 3D image of its internal structure. The device is basically composed by a radiation tube and a detector panel, which are fixed to a gantry that rotates all around the test subject. The micro-CT system is affected by several imperfections and problems, that might lead to serious artifacts that deteriorate the quality of the reconstructed image. In particular, two issues have been discussed in the present work: the source-panel geometric misalignment and the detector lag effect. The first problem concerns the consequences of systems where the different elements are not perfectly aligned to each other. The second issue regards the residual signal, left in the detector's sensor after a projection acquisition, which affects the following frames with ghost images. Both these arguments have been investigated to describe their characteristics and behaviour in a typical acquisition protocol. Then two correction methods have been presented and tested on a real micro-CT device to verify their effectiveness in the artifacts compensation. In the end, a comparison between images before and after the corrections is provided and future prospects are discussed.