In this thesis work, a design of 14-bit, 20MS/s segmented digital-to-analog converter (DAC) is presented. The segmented DAC uses switched-capacitor configuration to implement 8 (LSB) + 6 (MSB) segmented architecture to achieve high performance for minimum area. The implemented LSB DAC is based on quasi-passive pipelined DAC that has been proven to provide low power and high speed operation. Typically, capacitor matching is the best among all integrated circuit components but the mismatch among nominally equal value capacitors will introduce nonlinear distortion. By using dynamic element matching (DEM) technique in the MSB DAC, the nonlinearity caused by capacitor mismatch is greatly reduced. The output buffer employed direct charge transfer (DCT) technique that can minimize kT/C noise without increasing the power dissipation. This segmented DAC is designed and simulated in 0.18 μm CMOS technology, and the simulated core DAC block only consumes 403 μW. / Graduation date: 2012

Advances in electronic systems have lead to the demand for high resolution, high bandwidth Analog-to-Digital Converters (ADCs). Oversampled ADCs are well- known for high accuracy applications since they benefit from noise shaping and they usually do not need highly accurate components. However, as a consequence of oversampling, they have limited signal bandwidth. The signal bandwidth (BW) of oversampled ADCs can be increased either by increasing the sampling rate or reducing the oversampling ratio (OSR). Reducing OSR is a more promising method for increasing the BW, since the sampling speed is usually limited by the technology. The advantageous properties (e.g. low in-band quantization, relaxed accuracy requirements of components) of oversampled ADCs are usually diminished at lower OSRs and preserving these properties requires complicated and power hungry architectures. In this thesis, different combinations of delta-sigma and pipelined ADCs are explored and new techniques for designing oversampled ADCs are proposed. A Hybrid Delta-Sigma/Pipelined (HDSP) ADC is presented. This ADC uses a pipelined ADC as the quantizer of a single-loop delta-sigma modulator and benefits from the aggressive quantization of the pipelined quantizer at low OSRs. A Noise-Shaped Pipelined ADC is proposed which exploits a delta-sigma modulator as the sub-ADC of a pipeline stage to reduce the sensitivity to the analog imperfection. Three prototype ADCs were fabricated in 0.18μm CMOS technology to verify the effectiveness of the proposed techniques. The performance of these architectures is among the best reported for high bandwidth oversampled ADCs. / Graduation date: 2011

In recent years, the demand for alternatives to fossil fuels has risen dramatically, and ethanol fuel has become an important liquid fuel alternative globally. The most efficient mode of transportation of petroleum-based fuel is via pipelines, and due to the 300% increase in ethanol use in the U.S. in the past decade, a similar method of conveyance must be adopted for ethanol. Low-carbon, low-alloy pipeline steels like X52, X60, and X65 comprise the existing fuel transmission pipeline infrastructure. However, similar carbon steels, used in the ethanol processing and production industry, were found to exhibit stress corrosion cracking (SCC) in ethanol service. Prior work has shown that contaminants absorbed by the ethanol during distillation, processing or transport could be the possible determinants of SCC susceptibility; 200 proof ethanol alone was shown not to cause SCC in laboratory studies. To ensure the safety and integrity of the pipeline system, it was necessary to perform a mechanistic study of SCC of pipeline steel in fuel grade ethanol (FGE). The objective of this work was to determine the environmental factors relating to SCC of X65 steel in fuel grade ethanol (FGE) environments. To accomplish this, a systematic study was done to test effects of FGE feedstock and common contaminants and constituents such as water, chloride, dissolved oxygen, and organic acids on SCC behavior of an X65 pipeline steel. Slow strain rate tests (SSRT) were employed to evaluate and compare specific constituents' effects on crack density, morphology, and severity of SCC of X65 in FGE. SCC did not occur in commercial FGE environments, regardless of the ethanol feedstock. In both FGE and simulated fuel grade ethanol (SFGE), SCC of carbon steel was found to occur at low water contents (below 5 vol%) when chloride was present above a specific threshold quantity. Cl- threshold for SCC varied from 10ppm in FGE to approximately 1 ppm in SFGE. SCC of carbon steel was inhibited when oxygen was removed from solution via N2 purge or pHe was increased by addition of NaOH. During SSRT, in-situ¬ electrochemical measurements showed a significant role of film rupture in the SCC mechanism. Analysis of repassivation kinetics in mechanical scratch tests revealed a large initial anodic dissolution current spike in SCC-causing environments, followed by repassivation indicated by current transient decay. In the deaerated environments, repassivation did not occur, while in alkaline SFGE repassivation was significantly more rapid than in SCC-inducing SFGE. Composition and morphology of the passive film on X65 during static exposure tests was studied using X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM). Results showed stability of an air-formed native oxide under static immersion in neutral (pHe = 5.4) SFGE, and dissolution of the film when pHe was decreased to 4.3. XPS spectra indicated changes in film composition at high pHe (near 13) and in environments lacking sufficient water. In light of all results, a film-rupture anodic-dissolution mechanism is proposed in which local plastic strains facilitates local breakdown of the air-formed oxide film, causing iron to dissolve anodically. During crack propagation anodic dissolution occurs at the crack tip while crack walls repassivate preserving crack geometry and local stress concentration at the tip. It is also proposed that SCC can be mitigated by use of alkaline inhibitors that speed repassivation and promotes formation of a more protective Fe(OH)3 film.

Starting with tensor calculus and the variational form of the Hamiltonian functional, a generalized theory is formulated for doubly curved thin shells. The formulation avoids geometric approximations commonly adopted in other formulations. The theory is then specialized for cylindrical and toroidal shells as special cases, both of interest in the modeling of straight and elbow segments of pipeline systems. Since the treatment avoids geometric approximations, the cylindrical shell theory is believed to be more accurate than others reported in the literature. By adopting a set of consistent geometric approximations, the present theory is shown to revert to the well known Flugge shell theory. Another set of consistent geometric approximations is shown to lead to the Donnell-Mushtari-Vlasov (DMV) theory. A general closed form solution of the theory is developed for cylinders under general harmonic loads. The solution is then used to formulate a family of exact shape functions which are subsequently used to formulate a super-convergent finite element. The formulation efficiently and accurately captures ovalization, warping, radial expansion, and other shell behavioural modes under general static or harmonic forces either in-phase or out-of-phase. Comparisons with shell solutions available in Abaqus demonstrate the validity of the formulation and the accuracy of its predictions. The generalized thin shell theory is then specialized for toroidal shells. Consistent sets of approximations lead to three simplified theories for toroidal shells. The first set of approximations has lead to a theory comparable to that of Sanders while the second set of approximation has lead to a theory nearly identical to the DMV theory for toroidal shells. A closed form solution is then obtained for the governing equation. Exact shape functions are then developed and subsequently used to formulate a finite element. Comparisons with Abaqus solutions show the validity of the formulation for short elbow segments under a variety of loading conditions. Because of their efficiency, the finite elements developed are particularly suited for the analysis of long pipeline systems.

In recent decades, the truth commission has become a mechanism used by states to address historical injustices. However, truth commissions are rarely used in established democracies, where the commission of inquiry model is favoured. I argue that established democracies may be more amenable to addressing historical injustices that continue to divide their populations if they see the truth commission mechanism not as a unique mechanism particular to the transitional justice setting, but as a specialized form of a familiar mechanism, the commission of inquiry. In this framework, truth commissions are distinguished from other commissions of inquiry by their symbolic acknowledgement of historical injustices, and their explicit “social function” to educate the public about those injustices in order to prevent their recurrence. Given that Canada has established a Truth and Reconciliation Commission (TRC) on the Indian Residential Schools legacy, I consider the TRC’s mandate, structure and ability to fulfill its social function, particularly the daunting challenge of engaging the non-indigenous public in its work. I also provide a legal history of a landmark Canadian public inquiry, the Mackenzie Valley Pipeline Inquiry, run by Tom Berger. As his Inquiry demonstrated, with visionary leadership and an effective process, a public inquiry can be a pedagogical tool that promotes social accountability for historical injustices. Conceiving of the truth commission as a form of public inquiry provides a way to consider the transitional justice literature on truth commissions internationally along with the experiences of domestic commissions of inquiry to assemble strategies that may assist the current TRC in its journey.

In recent decades, the truth commission has become a mechanism used by states to address historical injustices. However, truth commissions are rarely used in established democracies, where the commission of inquiry model is favoured. I argue that established democracies may be more amenable to addressing historical injustices that continue to divide their populations if they see the truth commission mechanism not as a unique mechanism particular to the transitional justice setting, but as a specialized form of a familiar mechanism, the commission of inquiry. In this framework, truth commissions are distinguished from other commissions of inquiry by their symbolic acknowledgement of historical injustices, and their explicit “social function” to educate the public about those injustices in order to prevent their recurrence. Given that Canada has established a Truth and Reconciliation Commission (TRC) on the Indian Residential Schools legacy, I consider the TRC’s mandate, structure and ability to fulfill its social function, particularly the daunting challenge of engaging the non-indigenous public in its work. I also provide a legal history of a landmark Canadian public inquiry, the Mackenzie Valley Pipeline Inquiry, run by Tom Berger. As his Inquiry demonstrated, with visionary leadership and an effective process, a public inquiry can be a pedagogical tool that promotes social accountability for historical injustices. Conceiving of the truth commission as a form of public inquiry provides a way to consider the transitional justice literature on truth commissions internationally along with the experiences of domestic commissions of inquiry to assemble strategies that may assist the current TRC in its journey.

Starting with tensor calculus and the variational form of the Hamiltonian functional, a generalized theory is formulated for doubly curved thin shells. The formulation avoids geometric approximations commonly adopted in other formulations. The theory is then specialized for cylindrical and toroidal shells as special cases, both of interest in the modeling of straight and elbow segments of pipeline systems. Since the treatment avoids geometric approximations, the cylindrical shell theory is believed to be more accurate than others reported in the literature. By adopting a set of consistent geometric approximations, the present theory is shown to revert to the well known Flugge shell theory. Another set of consistent geometric approximations is shown to lead to the Donnell-Mushtari-Vlasov (DMV) theory. A general closed form solution of the theory is developed for cylinders under general harmonic loads. The solution is then used to formulate a family of exact shape functions which are subsequently used to formulate a super-convergent finite element. The formulation efficiently and accurately captures ovalization, warping, radial expansion, and other shell behavioural modes under general static or harmonic forces either in-phase or out-of-phase. Comparisons with shell solutions available in Abaqus demonstrate the validity of the formulation and the accuracy of its predictions. The generalized thin shell theory is then specialized for toroidal shells. Consistent sets of approximations lead to three simplified theories for toroidal shells. The first set of approximations has lead to a theory comparable to that of Sanders while the second set of approximation has lead to a theory nearly identical to the DMV theory for toroidal shells. A closed form solution is then obtained for the governing equation. Exact shape functions are then developed and subsequently used to formulate a finite element. Comparisons with Abaqus solutions show the validity of the formulation for short elbow segments under a variety of loading conditions. Because of their efficiency, the finite elements developed are particularly suited for the analysis of long pipeline systems.

Master thesis work at ITN (Department of Science and Technology) in the areas of A/D-construction and RF-circuit design. Major goal of project were to research suitable possibilities for implementations of direct conversion in transceivers operating in the 160MHz band, theoretic study followed by development of components in the construction environment Cadence. Suitable A/D- converter and other important parts were selected at the end of the theoretic study. Subsampling technique was applied to make A/D sample requirements more realistic to achieve. Besides lowering requirements on A/D-converter it allows a more simple construction, which saves more components than subsampling adds. Subsampling add extra noise, because of that an A/D-converter based on the RSD algorithm was chosen to improve error rate. To achieve high bit-processing rate compared to the used number of transistors, pipeline structure were selected as conversion method. The receiver was that part which gained largest attention because it’s the part which is most interesting to optimise. A/D-conversion is more difficult to construct than D/A conversion, besides there’s more to gain from eliminating mixers in the receiver than in the transmitter.

The profound and observable changes in the world, including globalization, in the last decades have weakened the state power vis-&agrave / -vis non-state actors. This process naturally, has marked down the state capacity to protect and promote internationally recognized human rights and fundamental freedoms. In this context, TNCs, the principle actors of economic globalization, not only threaten the enjoyment of human rights, but also challenge to the state-centric human rights understanding. This thesis claims that the state-centric paradigm has got difficulties to locate non-state actors that violate human rights. While this study proceeds from the premise that the state is the primary responsible actor, it cannot certainly be considered as the sole responsible actor for human rights. Likewise, the thesis suggests that a new international mechanism that holds also non-state actors, particularly TNCs, responsible for human rights needs to be established.

In all of the previous pipelining methods such as conventional pipelining, wave pipelining, and mesochronous pipelining, a data wave propagating on the combinational circuit is sampled whenever it arrives to a synchronization stage. In this study, a new wave-pipelining methodology named as Wave Component Sampling Method (WCSM), is proposed. In this method, only the component of a wave, whose maximum and minimum delay difference exceeds the tolerable value, is sampled, and the other components continue to propagate on the circuit. Therefore, the total number of registers required for synchronization decreases significantly. For demonstrating the effectiveness of the proposed WCSM, an 8x8 bit carry save In all of the previous pipelining methods such as conventional pipelining, wave pipelining, and mesochronous pipelining, a data wave propagating on the combinational circuit is sampled whenever it arrives to a synchronization stage. In this study, a new wave-pipelining methodology named as Wave Component Sampling Method (WCSM), is proposed. In this method, only the component of a wave, whose maximum and minimum delay difference exceeds the tolerable value, is sampled, and the other components continue to propagate on the circuit. Therefore, the total number of registers required for synchronization decreases significantly. For demonstrating the effectiveness of the proposed WCSM, an 8x8 bit carry save adder (CSA) multiplier is implemented using 0.18&micro / m CMOS technology. A generic transmission gate logic block with optimized output delay variation depending on the input pattern is designed and used in all of the sub blocks of the multiplier. Post layout simulation results show that, this multiplier can operate at a speed of 3GHz, using only 70 latches. Comparing with the mesochronous pipelining scheme, the number of the registers is decreased by 41% and the total power of the chip is also decreased by 9.5% without any performance loss. An ultra high speed full pipelined CSA multiplier with an operating frequency of 5GHz is also implemented with WCSM. The number of registers is decreased by 45%, and the power consumption of the circuit is decreased by 18.4% comparing with conventional or mesochronous pipelining methods. WCSM is also applied to different multiplier structures employing booth encoders, Wallace trees, and carry look-ahead adders. Comparing full pipelined 8x8 bit WCSM multiplier with the conventional pipelined multiplier, the number of registers in the implementation of booth encoder, Wallace tree, and carry look-ahead adder is decreased by 30%, 51%, and %62, respectively.