The primary purposes of this research were to identify construction factors most correlated to specific mechanical properties of cement-treated base (CTB) layers and to determine which construction factors exhibit comparatively high variability within individual construction sections of the two pavement reconstruction projects included in this study. In addition, differences between construction sections tested in this research were evaluated. The research focused on the construction of CTB layers in two pavement reconstruction projects in northern Utah, one along Interstate 84 (I-84) near Morgan and one along U.S. Highway 91 (US-91) near Richmond. The significant predictor variables associated with California bearing ratio (CBR), Clegg impact value (CIV), 7-day unconfined compressive strength (UCS), and 28-day UCS at the I-84 sites include reclaimed asphalt pavement (RAP) content; cement content; amounts of aggregate particles finer than the No. 8, No. 50, and No. 200 sieves; 7-day moisture content, and 28-day moisture content. The significant predictors of the same response variables on US-91 were in-situ moisture content, cement content, amount of aggregate particles finer than the No. 50 sieve, time between mixing and compaction in the field, dry density in the field, 7-day dry density, 7-day moisture content, 28-day dry density, and 28-day moisture content. The factors that were found to be the most variable on both I-84 and US-91 were CBR, cement content, time between mixing and compaction in the field, and time between mixing and compaction for each of the manually compacted specimens. On I-84, 16 of 27 factors were found to be significantly different between the sites, while 17 of 26 factors were found to be significantly different between the sites on US-91. The results of this research suggest that tighter specifications are warranted with respect to RAP content, cement content, and time between mixing and compaction. Concerning full depth recycling (FDR) projects, milling plans should be utilized to achieve improved uniformity in RAP content, and inspection protocols for encouraging improved control of cement content should be implemented during construction to ensure high-quality work. Compaction should be performed as soon as possible after mixing to minimize the adverse effects of cement hydration on the ability to achieve maximum dry density in the field.

Full-scale dynamic lateral load tests were performed on a pile cap with a dense silty sand backfill condition. Two hydraulic load actuators connected a test pile cap with a reaction cap. The load actuators incrementally loaded the test cap up to 50 mm of displacement. After each load increment, the displacement was held constant while an eccentric mass shaker induced dynamic loads under a ramping sequence from 1 Hz to 10 Hz. A baseline response was developed under a no backfill condition. Passive soil pressure was measured using pressure cells and tactile sensors. It was concluded that the presence of the backfill significantly increased the lateral load resistance of the pile-cap system, with the resistance nearly doubling at a 50 mm deflection level. After initial loading, the pile cap system experienced a loss in load resistance. In the case with backfill present, this relaxation generally represented a 10 to 15% loss in resistance. Additionally, after undergoing dynamic, cyclic loading, the resistance was approximately 40 to 80% of its initial value. Dynamic displacement amplitudes were on the order of 0 to 2 mm. Passive pressure from the backfill was observed to be non-linear with a concentration of pressure near the bottom of the pile cap. Rankine, Coulomb, and log-spiral earth pressure theories underestimated the passive earth pressure from the backfill by at least 30%. The natural frequency of the pile cap increased with increasing with static displacement level while placement of the backfill further increased the frequency of the pile cap. On average, the presence of the backfill increased the reloading stiffness of the pile cap by a factor of three to four, whereas the damping ratio increased by a factor of two. The dense silty sand backfill acting by itself on the face of the 1.12 m tall and 5.18 m wide pile cap face exhibited a reloading stiffness on the order of 120 to 250 kN/mm and a damping ratio of 30 to 70%. These damping ratios are significantly higher than that typical expected for structural materials but appear to be consistent with values for soils.

The research in this dissertation is divided between three different approaches for predicting the shear strength of reinforcement masonry shear walls. Each approach provides increasing accuracy and precision in predicting the shear strength of masonry walls. The three approaches were developed or validated using data from 353 wall tests that have been conducted over the past half century. The data were collected, scrutinized, and synthesized using principles of meta-analysis. Predictions made with current Masonry Standards Joint Committee (MSJC) shear strength equation are unconservative and show a higher degree of variation for partially-grouted walls. The first approach modifies the existing MSJC equation to account for the differences in nominal strength and uncertainty between fully- and partially-grouted walls. The second approach develops a new shear strength equation developed to perform equally well for both fully- and partially-grouted walls to replace and improve upon the current MSJC equation. The third approach develops a methodology for creating strut-and-tie models to analyze or design masonry shear walls. It was discovered that strut-and-tie modeling theory provides the best description of masonry shear wall strength and performance. The masonry strength itself provides the greatest contribution to the overall shear capacity of the wall and can be represented as diagonal compression struts traveling from the top of the wall to the compression toe. The shear strength of masonry wall is inversely related to the shear span ratio of the wall. Axial load contributes to shear strength, but to a lesser degree than what has been previously believed. The prevailing theory about the contribution of horizontal shear reinforcement was shown to not be correct and the contribution is much smaller than was originally assumed by researchers. Horizontal shear reinforcement principally acts by resisting diagonal tensile forces in the masonry and by helping to redistribute stresses in a cracked masonry panel. Vertical reinforcement was shown to have an effect on shear strength by precluding overturning of the masonry panel and by providing vertical anchorages to the diagonal struts.

The objective of this research was to measure and analyze the long-term modulus values of cement-treated base (CTB) layers constructed in Utah using microcracking. Because modulus values of pavement layers are among the most influential inputs affecting mechanistic-empirical pavement design, obtaining reasonable estimates of modulus values is critical. Testing was performed with a portable falling-weight deflectometer, also called a lightweight deflectometer, and modulus values were backcalculated with the computer program BAKFAA. Testing occurred at five asphalt pavement sites in northern Utah, where reconstruction with full-depth reclamation and cement stabilization, in the form of cement slurry, was performed approximately 2 to 14 years previously. Unconfined compressive strength (UCS) data collected for the CTB materials during earlier projects were compiled for all five sites. The correlation between backcalculated CTB modulus values, which ranged from 42 to 433 ksi, and 7-day UCS values, which ranged from 366 to 559 psi, was analyzed, and uniformity and sensitivity analyses were performed. Based on the results of this research, a new correlation is proposed for estimating the long-term modulus values of microcracked CTB layers constructed in a seasonally cold climate, such as northern Utah. For an average 7-day UCS of 450 psi, a CTB modulus value of 114 ksi would be estimated using this correlation, whereas a much higher modulus value of 630 ksi would be estimated from an existing correlation chart that was published in 1972 before microcracking was developed as a CTB construction practice. The results of the uniformity analyses indicate that statistically significant spatial variability in the CTB modulus values exists at each site. In comparison to a proposed maximum threshold coefficient of variation of 40 percent presented in the literature for aspects of CTB construction, the CTB modulus at all of the sites would be characterized as having low uniformity, with values ranging from 42.9 to 90.3 percent. The results of the sensitivity analyses indicate that backcalculated CTB modulus values are sensitive to typical deviations from design values that may occur in pavement layer thicknesses and suggest that CTB modulus estimation errors may range from -22,561 to 62,097 psi, or -3.73 to 10.81 percent, for pavements similar to those studied in this research when the actual asphalt and CTB layer thicknesses are different than the assumed values by up to 0.25 or 0.50 in., respectively.

OBJECTIVES: The purpose of this in vitro study is to measure and compare the accuracy of the conventional impression, the intraoral scanner, and the photogrammetry techniques for full-arch implant-supported dental prostheses at the abutment level. METHODS: An edentulous maxillary master model containing 6 implant abutment replicas (RP analog for screw-retained abutment straight from NobelReplace® Multi-unit Abutment Plus Replica) was fabricated. A reference STL of the master model was obtained using a desktop scanner (inEos X5, Dentsply Sirona) with high trueness and precision and served as the control STL. Three impression techniques were performed: the intraoral scanning (IOS) group (TRIOS 3 Battery Cart, 3Shape A/S), the photogrammetry (PTG) group (ICam 4D Generation 3, Imetric), and the conventional (CNV) group. Ten impressions from each group were tested. Scan bodies in each STL file acquired from the different impression techniques were converted to implant abutment replicas using a digital library. Three tests were completed to compare the different registration techniques. A 3D deviation test between the experimental group and the reference was done on an inspection software (IScan4D Dental Version 9.1.104; Imetric) using a “best fit” algorithm to obtain the root mean square values, and on another inspection software (IScan3D Dental Version 9.1.104; Imetric) using spatial similarity transformation. The second test was meant to assess the angular deviations of the implant abutment replicas using a reverse engineering software (Geomagic Control X 2020.1; 3D Systems). The final test for cross-arch distances was done on an inspection software (IScan3D Dental Version 9.1.104; Imetric) which allows to determine the 3-dimensional coordinates for each implant by using the origin point and compare the cross-arch distance deviations as well as deviations at the x-, y-, and z- coordination. Trueness and precision were the two parameters used to define the accuracy of a system. The term "trueness" was used to see how close the measurements from the experimental files of each group were to those of the reference file. The term "precision" was defined as to see how close the measurements of each experimental files were to each other within the same group. The 3D discrepancies were then calculated and the trueness and precision of the three impression techniques were assessed and compared statistically (α = 0.05). RESULTS: The root mean square of 3D deviation values through the ICP “best-fit” method showed statistically significant differences between the PTG and CNV group (p < .0001), and the PTG and IOS group (p < .0001). The CNV and IOS group did not show statistically significant differences (p = 0.8626) through the “best-fit” method, but significant differences were observed via the “spatial similarity” method (p = 0.0041). Both methods however showed the best results in terms of trueness for the PTG group, followed by the CNV group and least the IOS group. In terms of precision, PTG showed the best results, followed by the IOS group and least the CNV group. The angular deviation test using the “best-fit” alignment method showed that the PTG and CNV had no statistically significant difference (p = 0.7955) and were equivalent. However, both showed a statistically significant difference to the IOS group (p < .0001), which had the highest angular deviation. Finally, in terms of cross-arch distances, the photogrammetry group showed optimal results followed by the IOS group and then the CNV group. In general, the shorter the inter-arch distance, the lower the deviation was. A larger deviation was observed on longer inter-arch distances. Considering the deviations on the 3 axes of each implant, the CNV technique had the highest deviation in the X-axis (longitudinal) and the IOS technique showed the highest deviation on the Y-axis (lateral) and Z-axis (vertical). The PTG technique experienced significantly less deviation on the X-axis, Y-axis, and the Z-axis. CONCLUSION: Within the scope of this study, the photogrammetry technique reported the best accuracy in terms of trueness and precision of implant positions for complete-arch implant rehabilitation. Conventional impressions showed better accuracy results than intraoral scanning in the 3D deviations test and global angular deviation test, however the latter exhibited better results in terms of accuracy in terms of cross-arch distances test. / 2023-08-11T00:00:00Z

Future cellular networks, the so-called 5G, are expected to provide explosive data volumes and data rates. To meet such a demand, the research communities are investigating new wireless transmission technologies. One of the most promising candidates is in-band full-duplex communications. These communications are characterized by that a wireless device can simultaneously transmit and receive on the same frequency channel. In-band full-duplex communications have the potential to double the spectral efficiencywhen compared to current half duplex systems. The traditional drawback of full-duplex was the interference that leaks from the own transmitter to its own receiver, the so- called self-interference, which renders the receiving signal unsuitable for communication.However, recent advances in self-interference suppression techniques have provided high cancellation and reduced the self-interference to noise floor levels, which shows full-duplex is becoming a realistic technology component of advanced wireless systems. Although in-band full-duplex promises to double the data rate of existing wireless technologies, its deployment in cellular networks is challenging due to the large number of legacy devices working in half-duplex. A viable introduction in cellular networks is offered by three-node full-duplex deployments, in which only the base stations are full-duplex, whereas the user- or end-devices remain half-duplex. However, in addition to the inherent self-interference, now the interference between users, the user-to-user interference, may become the performance bottleneck, especially as the capability to suppress self-interference improves. Due to this new interference situation, user pairing and frequency channel assignment become of paramount importance, because both mechanisms can help to mitigate the user-to-user interference. It is essential to understand the trade-offs in the performance of full-duplex cellular networks, specially three-node full-duplex, in the design of spectral and energy efficient as well as fair mechanisms. This thesis investigates the design of spectral efficient and fair mechanisms to improve the performance of full-duplex in cellular networks. The novel analysis proposed in this thesis suggests centralized and distributed user pairing, frequency channel assignment and power allocation solutions to maximize the spectral efficiency and fairness in future full-duplex cellular networks. The investigations are based on distributed optimization theory with mixed integer-real variables and novel extensions of Fast-Lipschitz optimization. The analysis sheds lights on two fundamental problems of standard cellular networks, namely the spectral efficiency and fairness maximization, but in the new context of full-duplex communications. The results in this thesis provide important understanding in the role of user pairing, frequency assignment and power allocation, and reveal the special behaviourbetween the legacy self-interference and the new user-to-user interference. This thesis can provide input to the standardization process of full-duplex communications, and have the potential to be used in the implementation of future full-duplex in cellular networks. / <p>QC 20170403</p>

This dissertation provides a comprehensive methodology for accurate analysis and design of miniaturized radio frequency (RF) surface acoustic wave (SAW) duplexer package. Full-wave analysis based on the three dimensional (3-D) finite element method (FEM) is successfully applied to model the package. The die model is obtained by combining the acoustics and die busbars parasitics models. The acoustics model is obtained using the coupling-of-models (COM) technique. The die busbars, bonding wires and printed circuit board (PCB) are modeled using full-wave analysis. After that, the models of package, die, and bonding wires are assembled together to get the total response. To take into account the mutual couplings, the methodology is extended to model the package, die busbars, and bonding wires together. The advantages and disadvantages of the methodology are also discussed. Based on the methodology, the Korea personal communication system (KPCS) duplexer is analyzed and designed. The isolation of KPCS duplexer package is significantly improved by redesigning inner ground plane, bonding wire scheme and ground via. A KPCS duplexer package is designed and excellent transmitter to receiver isolation in the transmission band is achieved. Simulation and measurement results are compared, and excellent agreement is found. Although we focus on investigating the methods to improve the isolation, the passband performance is also improved. The methodology is also successfully used for flip chip duplexer. The simulation results from our assembling method match the measurement results very well. Optimization method is applied to improve the transmit band isolation. With the new package and die design, the transmit band isolation can be improved from -53.6 dB to -65.2 dB. Based on the new package, the effect of the Rx ground trace on the isolation is investigated and the transmit band isolation can achieve -67.3 dB with the modification of the Rx ground trace. The technique developed in this dissertation reduces the design cycle time greatly and can be applied to various RF SAW device packages.

Yes / A quasi-orthogonal space time block coding (QO-STBC) scheme that exploits Hadamard matrix properties is studied and evaluated. At first, an analytical solution is derived as an extension of some earlier proposed QO-STBC scheme based on Hadamard matrices, called diagonalized Hadamard space-time block coding (DHSBTC). It explores the ability of Hadamard matrices that can translate into amplitude gains for a multi-antenna system, such as the QO-STBC system, to eliminate some off-diagonal (interference) terms that limit the system performance towards full diversity. This property is used in diagonalizing the decoding matrix of the QOSTBC system without such interfering elements. Results obtained quite agree with the analytical solution and also reflect the full diversity advantage of the proposed QO-STBC system design scheme. Secondly, the study is extended over an interference-free QO-STBC multi-antenna scheme, which does not include the interfering terms in the decoding matrix. Then, following the Hadamard matrix property advantages, the gain obtained (for example, in 4x1 QO-STBC scheme) in this study showed 4-times louder amplitude (gain) than the interference-free QOSTBC and much louder than earlier DHSTBC for which the new approach is compared with.

This paper presents test results and code predictions of four continuously and two simply supported concrete slabs reinforced with basalt fibre reinforced polymer (BFRP) bars. One continuously supported steel reinforced concrete slab was also tested for comparison purposes. All slabs tested were 500 mm in width and 150 mm in depth. The simply supported slabs had a span of 2000 mm, whereas the continuous slabs had two equal spans, each of 2000 mm. Different combinations of under and over BFRP reinforcement at the top and bottom layers of slabs were investigated. The continuously supported BFRP reinforced concrete slabs exhibited larger deflections and wider cracks than the counterpart reinforced with steel. Furthermore, the over reinforced BFRP reinforced concrete slab at the top and bottom layers showed the highest load capacity and the least deflection of all BFRP slabs tested. All continuous BFRP reinforced concrete slabs failed owing to combined shear and flexure at the middle support region. ISIS-M03-07 and CSA S806-06 design guidelines reasonably predicted the deflection of the BFRP slabs tested. However, ACI 440-1R-06 underestimated the BFRP slab deflections and overestimated the moment capacities at mid-span and over support sections.

In manufacturing, requirements are an essential aspect of the development process. A requirements view provides a perspective on how requirements are incorporated into the design and architecture of a system. Requirements documents for different product versions at a company like Alstom contain operational scenarios and Given-When-Then requirements, a specific format for expressing functional requirements. Operational scenarios are examples of how the product will be used in real-world situations, and they can also be useful for identifying and specifying functional and nonfunctional requirements. Currently, operational scenarios are manually linked to Given-When-Then requirements. This thesis presents a conceptual design that streamlines the requirements engineering process and allows for easier linking operational scenarios to Given-When-Then requirements.