It is essential to consider what new technologies mean to the people who use them and the ways in which they are experienced and used. In the context of public transit services in Saskatoon, understanding what the recent changes from a manual to an electronic/automated system means to users and the broader community is critically important to the overall assessment of the service. Investigating users’ lived experiences and interpretations of technical artifacts is valuable to understanding socio-technical relations or the embodied interactions of humans and machines as “technologies-in-practice.” Research into socio-technical relations has primarily focused on large scale technological systems and expert practices while less attention has been paid to “seemingly mundane” technologies or technical artifacts routinely used in everyday life. At the same time, this preoccupation has overshadowed or downplayed the importance of exploring users’ experiences and interpretations of technologies. The goal of this research is to contribute to the sociological understanding of mundane technologies-in-practice and socio-technical relations more broadly. In order to gain insight into this relationship, this thesis focuses on bus riders’ (users) and the community’s perceptions of the Go-Pass smartcard and electronic fare system used by the public transit service in Saskatoon. The perspectives of Go-Pass users and community stakeholders (n=15) were investigated using qualitative semi-structured interviews to gain deeper understanding into the complex relationship between users and technologies. Drawing from Science and Technology Studies (STS) and the sociology of technology literature, I propose that a sociomaterial theoretical perspective following a mutual shaping framework offers insight into socio-technical relations. Both critical and feminist technology studies literature has been helpful for developing an understanding of the wider social and political contexts of technical use which underscores this study. In particular, the conceptual insights of “socio-technical assemblages” (Suchman, 2007) and “intra-action” (Barad, 2003) have been helpful tools for exploring agency, subjectivity and power which is key to uncovering the intricacies of socio-technical relations and human-machine interaction. The four main themes emerging from this study were: 1) shifting human-machine roles and relationships; 2) the socio-technical construction of the bus rider; 3) configuring users’ and technologies; and 4) structural issues and social justice implications of technologies-in-practice. The findings demonstrate that the use of this new system is mutually co-constructed by both social and technical factors whereby both the users and the technology inform perceptions and use. There was also the unexpected connection between users’ everyday situated uses, experiences and interpretations of the Go-Pass technologies to wider social-political contexts. There were a number of issues raised in relation to the implementation of the Go-Pass system which had negative effects or unintended social and technical consequences particularly for those most marginalized economically. At the same time, there were important benefits and positive effects on riders’ quality of life and use of the service. Finally, participants’ perspectives have contributed to understanding what the Go-Pass technologies mean to them, the ways in which they are used in practice and the ways in which the mixing of people and seemingly mundane technologies shape relations in everyday settings.

In today’s world the multi-standard wireless receivers are gaining more and more popularity. End-users want to access voice, data and streaming media from a single wireless terminal. An ideal approach for multi-standard receiver front-end is to digitize a wide band RF signal available from the antenna. All radio functions such as downconversion, demodulation and channel selection can be then performed in the digital domain. Analog to Digital Converter in such a case should guarantee very high linearity, speed and bandwidth specifications while consuming a lot of power. Unfortunately an ADC with such stringent requirements cannot be realized in today’s CMOS technology. In a typical receiver a mixer is used to downconvert the RF signal to baseband (or IF) before digitization is performed. A passive mixer is often used in this case to mitigate the effect of the low frequency flicker noise. Specially it can be a sampling mixer which also serves as a S/H circuit usually required for A/D conversion. In this thesis a lowpass sigma-delta converter with RF sampling is presented. The ΣΔ modulator is SC passive circuit plus comparator, so an operational amplifier usually needed to realize the integrator is avoided. To reduce the complexity, the sampling mixer in front of the modulator is merged with the passive loop filter. As a result the sampling mixer is closed in the modulator loop, so the overall linearity of the frontend is improved to some extent. Downconversion is combined with digitization that reduces the circuit complexity as well.The challenges while digitizing high frequency RF signal are discussed in details. Switches required to realize the loop filter are very critical and tend to be nonlinear. Parasitic effects associated with MOS transistors strongly show up at GHz frequencies. Optimized transistor sizes are obtained through simulation while addressing the speed and linearity trade-off. Another major challenge is the kT/C noise that is the real bottleneck in high frequency SC circuit design. A thermal noise model for ΣΔ-modulator with second-order loop filter is presented and it is shown that a passive ΣΔ-modulator is  in fact thermal noise limited rather than quantization noise limited. It is because the capacitor values are limited by the very high sampling frequency used in this case.The downconverting lowpass ΣΔ modulator with second order SC passive loop filter and 1-bit quantizer is simulated at transistor level in 90nm CMOS process. This modulator can operate at very high sampling frequency upto 4GHz and can sample RF signal with carrier of upto 4GHz as well. The designed ΣΔ modulator is flexible and supports sub-sampling by 2 to 8 (fs = 500MHz, ... 2GHz). Besides, the presented design is very power efficient as it does not use OpAmps – which consume most of the power in the typical ΣΔ modulators. From schematic simulation on average, signal-to-noise and distortion ratio (SNDR) of 52 dB is obtained (ENOB = 8.3). SNDR results does not vary much for three different cases of baseband digitalization, RF sampling and RF sub-sampling. This SNDR value seems to be a good number for a passive sigma-delta modulator. The detailed simulation results for the three cases discussed in the thesis work shown that, the modulator performs equally well for a wide range of sampling and RF signal frequencies.

The vibration of and wave propagation in periodic cellular structures are analyzed. Cellular structures exhibit a number of desirable multifunctional properties, which make them attractive in a variety of engineering applications. These include ultra-light structures, thermal and acoustic insulators, and impact amelioration systems, among others. Cellular structures with deterministic architecture can be considered as example of periodic structures. Periodic structures feature unique wave propagation characteristics, whereby elastic waves propagate only in specific frequency bands, known as "pass band", while they are attenuated in all other frequency bands, known as "stop bands". Such dynamic properties are here exploited to provide cellular structures with the capability of behaving as directional, pass-band mechanical filters, thus complementing their well documented multifunctional characteristics. This work presents a methodology for the analysis of the dynamic behavior of periodic cellular structures, which allows the evaluation of location and spectral width of propagation and attenuation regions. The filtering characteristics are tested and demonstrated for structures of various geometry and topology, including cylindrical grid-like structures, Kagom and eacute; and tetrhedral truss core lattices. Experimental investigations is done on a 2-D lattice manufactured out of aluminum. The complete wave field of the specimen at various frequencies is measured using a Scanning Laser Doppler Vibrometer (SLDV). Experimental results show good agreement with the methodology and computational tools developed in this work. The results demonstrate how wave propagation characteristics are defined by cell geometry and configuration. Numerical and experimental results show the potential of periodic cellular structures as mechanical filters and/or isolators of vibrations.

High-pass filtering that is one of the most efficient methods in removing long-period noise of accelerograms is investigated for its effect on nonlinear oscillator deformation response. Within this context, uncertainty in filter cut-off periods that would significantly modify the low-frequency content of accelerograms come into prominence for obtaining reliable long-period displacement response. Analog and digital ground-motion records from recently compiled Turkish strong-motion database are used and these records are high-pass filtered with a consistent methodology by randomly generated filter cut-offs that represent different filter cut-off decisions of the analysts. The uncertainty in inelastic spectral and residual displacements (SDIE and SDR, respectively) due to variations in filter cut-offs is examined to derive the usable period ranges where the effect of high-pass filtering is tolerable. Non-degrading, stiffness degrading and stiffness and strength degrading oscillator behavior are considered in these analyses. The level of nonlinear behavior in single degree of freedom (SDOF) response is described by varying the yield strength (R, normalized yield strength) and displacement ductility (&micro / ) levels. The usable period ranges that depend on magnitude, recording quality, level of inelasticity and level of degradation are determined for SDIE through robust probabilistic methodologies.

In modern broadband microwave applications, receivers are very sensitive to interference signals which can come from the system itself or from hostile emitters. Electronically tunable bandstop filters can be used to eliminate these interference signals with adaptation to changing frequency conditions. In this thesis, electronically tunable bandstop filter design techniques are investigated for microwave frequencies. The aim is to find filter topologies which allow narrowband bandstop or &lsquo / notch&rsquo / filter designs with low-Q resonators and with tuning capability. Tunability will be provided by the use of electronically tunable capacitors, specifically varactor diodes. For this purpose, firstly direct bandstop filter techniques are investigated and their performances are analyzed. Then phase cancellation approach, which enables high quality bandstop filter design with lossy circuit elements, is introduced and analyzed. Lastly, a novel notch filter design technique called as all-pass filter approach is introduced. This approach allows a systematic design method and enables to design very good tunable notch filter characteristics with low-Q resonators. Three filter topologies using this approach are given and their performances are analyzed. Also prototype tunable notch filters operating in X-Band are designed and implemented by using these three topologies.

The main aim of this thesis is to explain the inflation dynamics in Turkey within a theoretically consistent empirical framework. The New Keynesian Phillips Curve (NKPC) is chosen as the basis model for our analysis because, by describing the inflation process within an intertemporal optimizing dynamic general equilibrium model, it provides a rigorous analytical groundwork for credible welfare and policy analysis. We have contributed to the literature by developing a NKPC formulation that is novel in the literature: A constant elasticity of substitution (CES) type of production function incorporating imported and domestically produced intermediate goods was combined with incomplete exchange rate pass through to import prices. The short-run inflation dynamics were analyzed within the context of this new specification by estimating the model&rsquo / s highly nonlinear structural parameters that capture the price-setting behavior in Turkey for period 1988:1 - 2009:4. Our findings suggest that this NKPC formulation can explain the 1994 and 2000-01 crises as well as the current environment of low inflation achieved with the adoption of the implicit and fully fledged inflation targeting regimes quite well. As a policy application we explored the effects of the inflation targeting framework adopted after the 2000-01 crises on the parameters characterizing the inflation process in Turkey. The subsample econometric results suggested that the inflation targeting framework applied was quite successful in decreasing inflation inertia in Turkey. Thus, should the success of the inflation targeting regime continue, this should be taken as an opportunity to reduce inflation substantially with very low output losses.

In this study, the effects of CBRT monetary policy decisions on the consumer, automobile, housing and commercial loans of the banks during the period from the early of 2004 to the middle of 2011 are examined. In order to perform this study, it is benefited from weekly weighted average loan interest rate data of the banks, which is the data having the highest frequency that could be obtained from the electronic data distribution system of CBRT. Monetary policy instruments of Central Bank may change in the course of time or monetary policy could be executed by more than one instrument. Therefore, as the political interest rate would be insufficient in the calculation of the effect of monetary policy on loan interest rates of the banks, Government Dept Securities&rsquo / premiums are used instead of the political interest rates in this study to make it reflect the policies of central bank more clearly as a whole. Among the Government Dept Securities that have different maturity structure, benchmark bonds that are adapted to the expected political interest rate changes and that react to the unexpected interest rate changes at the high rate (reaction coefficient 0.983) are used. In order to weight the cointegration relation between interest rates, unrestricted error correction model is established and it is determined by Bound Test that there is a long-term relation between each interest rate and interest rate of benchmark bond. After a cointegration relation is determined among the serials, autoregressive distributed lag model is used to determine the level of transitivity and it is determined that monetary policy decisions affect the banking interest rate at 77% level and by 13 weeks delay on average.

The mainstream of current VLSI design and logic synthesis is based on traditional CMOS logic circuits. However, in the past two decades, various new logic circuit design styles based on pass-transistor logic (PTL) have been proposed. Compared with CMOS circuits, these PTL-based circuits are claimed to have better results in area, speed, and power in some particular applications, such as adder and multiplier designs. Since most current automatic logic synthesis tools (such as Synopsys Design Compiler) are based on conventional CMOS standard cell library, the corresponding logic minimization for CMOS logic cannot be directly employed to generate efficient PTL circuits. In this dissertation, we develop two novel PTL synthesizers that can efficiently generate PTL-based circuits. One is based on pure PTL cells; the other mixes CMOS and PTL cells in the standard cell library to achieve better performance in area, speed, and power. Since PTL-based circuits are constructed by only a few basic PTL cells, the layouts in PTL cells can be easily updated to design large SoC systems as the process technology migrates rapidly in current Nano technology era. The proposed PTL logic synthesis flows employ the popular Synopsys Design Compiler (DC) to perform logic translation and minimization based on the standard cell library composed of PTL and CMOS cells, thus, the PTL design flow can be easily embedded in the standard cell-based ASIC design flow. In this dissertation, we also discuss PTL-based designs of some fundamental hardware components. Furthermore, the proposed PTL cell library is used to synthesize large processor systems in applications of computer arithmetic and 3D graphics.

The paper describes how a two-dimensional absolute measuring system can explicitly be realized. The theoretical background, the experimental setup, the evaluation algorithm, and the results of measurement are discussed in detail.

Univ., Diss.--Zugl.: Oslo, 2007.