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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
101

Empirical design of span openings in weak rock

Ouchi, Andrea Miyuki 11 1900 (has links)
This thesis presents ground control best practices in weak rock environments including an augmentation to the existing Span Design curve by adding 463 case histories of RMR76 values ranging from 25 to 60. A Neural Network analysis of this data has been added and compared to the existing Span Design data of 292 case histories. Ground support is almost always used in weak rock environments, though the type of support used can vary widely. The development of the weak rock augmented Span Design Curve has also been calibrated to four different support categories; Category A: Pattern Friction Sets, Category B: Pattern Friction Sets with Spot Bolting of Rebar, Category C: Pattern Friction Sets with Pattern Rebar Bolts and Category D: Cablebolting, Shotcrete, Spiling, Timber Sets or Underhand Cut and Fill. Category A is considered “Unsupported” with an average Factor of Safety less than 1.2. Categories B, C and D are considered “Supported” with average Factors of Safety greater than 1.2. All categories are compared the original Critical Span Design Curve presented by Lang (1994). However, only Category A can be accurately compared to the original Critical Span Design Curve as it is “Unsupported” as well. Category A yields good results, however, Categories B, C and D do not, but still demonstrate that spans can remain stable at lower RMR76 values. Design of underground man-entry type excavations in North America relies heavily upon empirical analysis. This design requires a higher Factor of Safety than other non-man entry type excavations. A comparison of the calculated ½ span failure Factor of Safety between all the categories is also presented. The contribution this research provides to the mining industry is the "Unsupported" Weak Rock Updated Span Design Curve and awareness pertaining to the potentially detrimental effects of using resin grounted rebar in weak rock masses and the false sense of security that the use of resin grouted rebar may instill. It is also shown that spans in the “Unstable” zone of the new “Unsupported” Weak Rock Updated Span Design Curve can possibly be stabilized if detailed engineering design is applied to obtain “Supported” status.
102

Partial ordering of weak mutually unbiased bases in finite quantum systems

Oladejo, Semiu Oladipupo January 2015 (has links)
There has being an enormous work on finite quantum systems with variables in Zd, especially on mutually unbiased bases. The reason for this is due to its wide areas of application. We focus on partial ordering of weak mutually un-biased bases. In it, we studied a partial ordered relation which exists between a subsystem ^(q) and a larger system ^(d) and also, between a subgeometry Gq and larger geometry Gd. Furthermore, we show an isomorphism between: (i) the set {Gd} of subgeometries of a finite geometry Gd and subsets of the set {D(d)} of divisors of d. (ii) the set {hd} of subspaces of a finite Hilbert space Hd and subsets of the set {D(d)} of divisors of d. (iii) the set {Y(d)} of subsystems of a finite quantum system ^(d) and subsets of the set {D(d)} of divisors of d. We conclude this work by showing a duality between lines in finite geometry Gd and weak mutually unbiased bases in finite dimensional Hilbert space Hd.
103

Weak and periodical solutions of the navier-stokes equation in noncylindrical domains

Quiroga Gonzáles, Cruz Sonia, Limaco, Juan, Gamboa, Pedro, Barreto, Rioco K. 25 September 2017 (has links)
We consider the Navier Stokes equation in noncylindrical domain and prove the existence of weak and periodical solutions.
104

Pensiero debole e tempo do espírito em Gianni Vattimo / Pensiero debole and time of the spirit in Gianni Vattimo

Oliveira, Francisco Elvis Rodrigues January 2017 (has links)
OLIVEIRA, Francisco Elvis Rodrigues. Pensiero debole e tempo do espírito em Gianni Vattimo. 2017. 141f. – Dissertação (Mestrado) – Universidade Federal do Ceará, Programa de Pós-Graduação em Filosofia, Fortaleza (CE), 2017. / Submitted by Gustavo Daher (gdaherufc@hotmail.com) on 2017-04-18T12:24:45Z No. of bitstreams: 1 2017_dis_ feroliveira.pdf: 930553 bytes, checksum: a885a01846b8d76887e17ea577335204 (MD5) / Approved for entry into archive by Márcia Araújo (marcia_m_bezerra@yahoo.com.br) on 2017-04-18T15:12:16Z (GMT) No. of bitstreams: 1 2017_dis_ feroliveira.pdf: 930553 bytes, checksum: a885a01846b8d76887e17ea577335204 (MD5) / Made available in DSpace on 2017-04-18T15:12:16Z (GMT). No. of bitstreams: 1 2017_dis_ feroliveira.pdf: 930553 bytes, checksum: a885a01846b8d76887e17ea577335204 (MD5) Previous issue date: 2017 / Esta dissertação pretende examinar, a partir da perspectiva do pensamento fraco de Gianni Vattimo, a questão do retorno do religioso no contexto contemporâneo compreendido como pós-modernidade e como tal fenômeno é por ele compreendido como realização de uma era do Espírito. De sua perspectiva, Vattimo realiza uma reflexão a partir da dissolução da metafísica e das grandes narrativas, identificando estes elementos como características da modernidade e, a dissolução destes, como sendo a passagem crítica para o pós-moderno. À luz da aproximação que Vattimo faz de Nietzsche e Heidegger, os respectivos anúncios da morte de Deus e o do fim da metafísica, ganham relevo para sua abordagem sobre o retorno da religião e a proposta de um cristianismo não religioso. Uma vez que Vattimo associa a metafísica com a violência e a crença tradicional associa-se, por sua vez, com a metafísica, este trabalho tenciona demonstrar que a tese do pensamento fraco de Gianni Vattimo surge como agente redutor desta violência metafísica.
105

Precise Measurement of the Photon Directional Asymmetry in the $\vec{n}p\rightarrow d\gamma$ Reaction

January 2017 (has links)
abstract: This work presents analysis and results for the NPDGamma experiment, measuring the spin-correlated photon directional asymmetry in the $\vec{n}p\rightarrow d\gamma$ radiative capture of polarized, cold neutrons on a parahydrogen target. The parity-violating (PV) component of this asymmetry $A_{\gamma,PV}$ is unambiguously related to the $\Delta I = 1$ component of the hadronic weak interaction due to pion exchange. Measurements in the second phase of NPDGamma were taken at the Oak Ridge National Laboratory (ORNL) Spallation Neutron Source (SNS) from late 2012 to early 2014, and then again in the first half of 2016 for an unprecedented level of statistics in order to obtain a measurement that is precise with respect to theoretical predictions of $A_{\gamma,PV}=O(10^{-8})$. Theoretical and experimental background, description of the experimental apparatus, analysis methods, and results for the high-statistics measurements are given. / Dissertation/Thesis / Doctoral Dissertation Physics 2017
106

Type theoretic weak factorization systems

North, Paige Randall January 2017 (has links)
This thesis presents a characterization of those categories with weak factorization systems that can interpret the theory of intensional dependent type theory with Σ, Π, and identity types. We use display map categories to serve as models of intensional dependent type theory. If a display map category (C, D) models Σ and identity types, then this structure generates a weak factorization system (L, R). Moreover, we show that if the underlying category C is Cauchy complete, then (C, R) is also a display map category modeling Σ and identity types (as well as Π types if (C, D) models Π types). Thus, our main result is to characterize display map categories (C, R) which model Σ and identity types and where R is part of a weak factorization system (L, R) on the category C. We offer three such characterizations and show that they are all equivalent when C has all finite limits. The first is that the weak factorization system (L, R) has the properties that L is stable under pullback along R and all maps to a terminal object are in R. We call such weak factorization systems type theoretic. The second is that the weak factorization system has what we call an Id-presentation: it can be built from certain categorical structure in the same way that a model of Σ and identity types generates a weak factorization system. The third is that the weak factorization system (L, R) is generated by a Moore relation system. This is a technical tool used to establish the equivalence between the first and second characterizations described. To conclude the thesis, we describe a certain class of convenient categories of topological spaces (a generalization of compactly generated weak Hausdorff spaces). We then construct a Moore relation system within these categories (and also within the topological topos) and thus show that these form display map categories with Σ and identity types (as well as Π types in the topological topos).
107

Weak delocalization due to long-range interaction for two electrons in a random potential chain

Römer, R. A., Schreiber, M. 30 October 1998 (has links) (PDF)
We study two interacting particles in a random potential chain by a transfer matrix method which allows a correct handling of the symmetry of the two- particle wave function, but introduces an artificial ¨bag¨ interaction. The dependence of the two-particle localization length lambta 2on disorder, interaction strength and range is investigated. Our results demonstrate that the recently proposed enhancement of lambta 2 as compared to the results for single particles is vanishingly small for a Hubbard interaction. For longer-range interactions, we observe a small enhancement but with a different disorder dependence than proposed previously.
108

Galaxy cluster luminosities and colours, and their dependence on cluster mass and merger state

Mulroy, Sarah L., McGee, Sean L., Gillman, Steven, Smith, Graham P., Haines, Chris P., Démoclès, Jessica, Okabe, Nobuhiro, Egami, Eiichi 12 1900 (has links)
We study a sample of 19 galaxy clusters in the redshift range 0.15 < z < 0.30 with highly complete spectroscopic membership catalogues (to K < K*(z) + 1.5) from the Arizona Cluster Redshift Survey, individual weak-lensing masses and near-infrared data from the Local Cluster Substructure Survey, and optical photometry from the Sloan Digital Sky Survey. We fit the scaling relations between total cluster luminosity in each of six bandpasses (grizJK) and cluster mass, finding cluster luminosity to be a promising mass proxy with low intrinsic scatter sigma ln (L|M) of only similar to 10-20 per cent for all relations. At fixed overdensity radius, the intercept increases with wavelength, consistent with an old stellar population. The scatter and slope are consistent across all wavelengths, suggesting that cluster colour is not a function of mass. Comparing colour with indicators of the level of disturbance in the cluster, we find a narrower variety in the cluster colours of 'disturbed' clusters than of 'undisturbed' clusters. This trend is more pronounced with indicators sensitive to the initial stages of a cluster merger, e.g. the Dressler Schectman statistic. We interpret this as possible evidence that the total cluster star formation rate is 'standardized' in mergers, perhaps through a process such as a system-wide shock in the intracluster medium.
109

Weak-lensing mass calibration of redMaPPer galaxy clusters in Dark Energy Survey Science Verification data

Melchior, P., Gruen, D., McClintock, T., Varga, T. N., Sheldon, E., Rozo, E., Amara, A., Becker, M. R., Benson, B. A., Bermeo, A., Bridle, S. L., Clampitt, J., Dietrich, J. P., Hartley, W. G., Hollowood, D., Jain, B., Jarvis, M., Jeltema, T., Kacprzak, T., MacCrann, N., Rykoff, E. S., Saro, A., Suchyta, E., Troxel, M. A., Zuntz, J., Bonnett, C., Plazas, A. A., Abbott, T. M. C., Abdalla, F. B., Annis, J., Benoit-Lévy, A., Bernstein, G. M., Bertin, E., Brooks, D., Buckley-Geer, E., Carnero Rosell, A., Carrasco Kind, M., Carretero, J., Cunha, C. E., D’Andrea, C. B., da Costa, L. N., Desai, S., Eifler, T. F., Flaugher, B., Fosalba, P., García-Bellido, J., Gaztanaga, E., Gerdes, D. W., Gruendl, R. A., Gschwend, J., Gutierrez, G., Honscheid, K., James, D. J., Kirk, D., Krause, E., Kuehn, K., Kuropatkin, N., Lahav, O., Lima, M., Maia, M. A. G., March, M., Martini, P., Menanteau, F., Miller, C. J., Miquel, R., Mohr, J. J., Nichol, R. C., Ogando, R., Romer, A. K., Sanchez, E., Scarpine, V., Sevilla-Noarbe, I., Smith, R. C., Soares-Santos, M., Sobreira, F., Swanson, M. E. C., Tarle, G., Thomas, D., Walker, A. R., Weller, J., Zhang, Y. 08 1900 (has links)
We use weak-lensing shear measurements to determine the mean mass of optically selected galaxy clusters in Dark Energy Survey Science Verification data. In a blinded analysis, we split the sample of more than 8000 redMaPPer clusters into 15 subsets, spanning ranges in the richness parameter 5 <= lambda <= 180 and redshift 0.2 <= z <= 0.8, and fit the averaged mass density contrast profiles with a model that accounts for seven distinct sources of systematic uncertainty: shear measurement and photometric redshift errors; cluster-member contamination; miscentring; deviations from the NFW halo profile; halo triaxiality and line-of-sight projections. We combine the inferred cluster masses to estimate the joint scaling relation between mass, richness and redshift, M(lambda, z). M-0 lambda(F) (1 + z)(G). We find M-0 equivalent to M-200m vertical bar lambda = 30, z = 0.5 = [2.35 +/- 0.22 (stat) +/- 0.12 (sys)] x 10(14) M circle dot, with F = 1.12 +/- 0.20 (stat) +/- 0.06 (sys) and G = 0.18 +/- 0.75 (stat) +/- 0.24 (sys). The amplitude of the mass-richness relation is in excellent agreement with the weak-lensing calibration of redMaPPer clusters in SDSS by Simet et al. and with the Saro et al. calibration based on abundance matching of SPT-detected clusters. Our results extend the redshift range over which the mass-richness relation of redMaPPer clusters has been calibrated with weak lensing from z <= 0.3 to z <= 0.8. Calibration uncertainties of shear measurements and photometric redshift estimates dominate our systematic error budget and require substantial improvements for forthcoming studies.
110

A 2500 deg2 CMB Lensing Map from Combined South Pole Telescope and Planck Data

Omori, Y., Chown, R., Simard, G., Story, K. T., Aylor, K., Baxter, E. J., Benson, B. A., Bleem, L. E., Carlstrom, J. E., Chang, C. L., Cho, H-M., Crawford, T. M., Crites, A. T., Haan, T. de, Dobbs, M. A., Everett, W. B., George, E. M., Halverson, N. W., Harrington, N. L., Holder, G. P., Hou, Z., Holzapfel, W. L., Hrubes, J. D., Knox, L., Lee, A. T., Leitch, E. M., Luong-Van, D., Manzotti, A., Marrone, D. P., McMahon, J. J., Meyer, S. S., Mocanu, L. M., Mohr, J. J., Natoli, T., Padin, S., Pryke, C., Reichardt, C. L., Ruhl, J. E., Sayre, J. T., Schaffer, K. K., Shirokoff, E., Staniszewski, Z., Stark, A. A., Vanderlinde, K., Vieira, J. D., Williamson, R., Zahn, O. 07 November 2017 (has links)
We present a cosmic microwave background (CMB) lensing map produced from a linear combination of South Pole Telescope (SPT) and Planck temperature data. The 150 GHz temperature data from the 2500 deg(2) SPT-SZ survey is combined with the Planck 143 GHz data in harmonic space to obtain a temperature map that has a broader l coverage and less noise than either individual map. Using a quadratic estimator technique on this combined temperature map, we produce a map of the gravitational lensing potential projected along the line of sight. We measure the auto-spectrum of the lensing potential C-L(phi phi), and compare it to the theoretical prediction for a.CDM cosmology consistent with the Planck 2015 data set, finding a best-fit amplitude of 0.95(-0.06)(+0.06) (stat.)(-0.01)(+0.01)+ (sys.). The null hypothesis of no lensing is rejected at a significance of 24 sigma. One important use of such a lensing potential map is in cross-correlations with other dark matter tracers. We demonstrate this cross-correlation in practice by calculating the cross-spectrum, C-L(phi) G, between the SPT+ Planck lensing map and Wide-field Infrared Survey Explorer (WISE) galaxies. We fit C-L(phi G) to a power law of the form p(L) = a(L/L-0)(-b) with a, L-0, and b fixed, and find eta(phi G) = C-L(phi G)/p(L) = 0.94(-0.04)(+0.04), which is marginally lower, but in good agreement with eta(phi G) = 1.00-(+0.02)(0.01), the best-fit amplitude for the cross-correlation of Planck-2015 CMB lensing and WISE galaxies over similar to 67% of the sky. The lensing potential map presented here will be used for cross-correlation studies with the Dark Energy Survey, whose footprint nearly completely covers the SPT 2500 deg(2) field.

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