319 research outputs found
The George H.N. Luhrs Family in Phoenix and Arizona, 1847-1984
No full textThe detailed memoir of the Luhrs Family's businesses and personal activities in Phoenix and elsewhere.Digitized in December 2014 from copy 71 of 150 copies produced with the generous support of the Luhrs Family Endowment
The Contradiction and inexpressibility in Ch'an Kung-an (Koan)
No full textThere are three types of Ch’an kung-an that often bewilder Buddhologists; namely, (1)the contradictory, (2)the inexpressible, and (3)mixture of the two. D. T. Suzuki and the scholars influenced by him, for example, E. Fromm, think that these three types of kung-an imply the truth realized by Ch’an masters, the truth which goes beyond daily language and logic. However, as the author points out, there are two traditions in Ch’an School: (1)the “Buddha-nature” tradition based on the La?k?vat?ra S?tra, and (2)the prajna tradition based on the Diamond S?tra. Suzuki and Formm’s interpretation only emphasizes the first tradition and ignores the second one. According to the second tradition, the contradiction and inexpressibility of kung-an may seem to indicate the truth of non-existence-??nyat?, not necessarily indicating the truly existing “Buddha-nature”
Waterflood-induced hydraulic fracturing
No full textCivil EngineeringCivil Engineering and Geoscience
Book Review: The Mammals of the Southern African Subregion
No full textBook Title: The Mammals of the Southern African SubregionBook Author: Reay H.N. SmithersUniversity of Pretoria, Pretoria, 1983. 736 pp.
Mosses new to Hong Kong (1)
No full textTen moss species - Garkea flexuosa (Griffith) Marg. & Nork., Campylopus laxitextus Lac., Fissidens dubius P. Beauv., Fissidens ceylonensis Dozy & Molk, Fissidens maceratus Mitt., Philonotis thwaitesii Mitt., Isopterygium minutirameum (C. Muell.)Jaeg., Homalia trichomanoides (Hedw.) B.S.G., Pogonatum neesii (C. Muell.) Dozyand Polytrichum formosum Hedw. are reported new to Hong Kong. Among them, five are new to Guangdong Province of China
Consistency of Bayesian inference with Gaussian process priors for a parabolic inverse problem
No full textWe consider the statistical non-linear inverse problem of recovering the absorption term f > 0 in the heat equation {∂tu-12Δu+fu=0onO×(0,T)u=gon∂ O×(0,T)u(·,0)=u0onO, where O ϵ ℝd is a bounded domain, T < ∞ is a fixed time, and g, u 0 are given sufficiently smooth functions describing boundary and initial values respectively. The data consists of N discrete noisy point evaluations of the solution u f on O×(0,T) . We study the statistical performance of Bayesian nonparametric procedures based on a large class of Gaussian process priors. We show that, as the number of measurements increases, the resulting posterior distributions concentrate around the true parameter generating the data, and derive a convergence rate for the reconstruction error of the associated posterior means. We also consider the optimality of the contraction rates and prove a lower bound for the minimax convergence rate for inferring f from the data, and show that optimal rates can be achieved with truncated Gaussian priors.Statistic
The Shortest Path Problem on Real Road Networks: Theory, Algorithms and Computations
No full textThis thesis contains the following subjects: - Several shortest path algorithms, both label-setting and label-correcting; - Unidirectional and bidirectional methods; - A* algorithms; - Symmetric and balanced estimators; - Preprocessing techniques. This thesis contains an elaborate, comparative evaluation of the various methods described. Bidirectional A* algorithms are commonly based on balanced heuristic estimators, since such estimators can easily be embedded in a bidirectional variant of Dijkstra's algorithm. In this thesis a check is provided, such that symmetric estimators can compete with balanced estimators. If these estimators are based on Euclidean distances, the work can be divided over the forward and backward searches with the use of scalar projections. This way, symmetric estimators are even prefered over balanced estimators. A well-known preprocessing technique includes the use of landmarks. If the estimators are based on landmarks, a balanced approach turns out to be faster than a symmetric approach. In this thesis, an initial step is proposed in a unidirectional A*-algorithm, which uses a landmark-based estimator, in order to decrease the running time of that algorithm. For one of the preprocessing techniques described, unidirectional methods are preferred over bidirectional methods. It is that particular preprocessing technique where the proposed initial step will prove an additional value.EWIElectrical Engineering, Mathematics and Computer Scienc
X-Ray Tomography: An Inverse Problem
No full textThis thesis aims at introducing the reader to the mathematical concepts behind the imaging technique X-ray tomography, commonly known as a CT scan. It includes the derivation of the filtered and unfiltered backprojection reconstruction methods for noise-free data. It was concluded that for noisy data, X-ray tomography is an ill-posed, and therefore unstable, inverse problem that needs regularization in order to produce adequate reconstructions. The methods of truncated singular value decomposition regularization and Tikhonov regularization are derived, analyzed and compared using simulated as well as real-life data. It was found that both methods can produce stable reconstructions, but that Tikhonov regularization is less sensitive to parameter choice.Applied Mathematic
Using Benford's Law for wavelet coefficients to differentiate images: Het toepassen van Benford's Law op wavelet coëfficiënten om afbeeldingen te onderscheiden
No full textThis thesis explores the application of Benford's Law to wavelet coefficients derived from the Discrete Wavelet Transform (DWT) of images, aiming to provide a novel method for image differentiation. The study focuses on the DWT, specifically utilizing Haar and Daubechies wavelets, to decompose an image into approximation and detail coefficients. Benford's Law, predicting the frequency distribution of leading digits in natural datasets, is applied to the detail coefficients. The research investigates whether this approach can differentiate natural images from other genres, such as paintings or cartoons. The thesis provides a comprehensive understanding of wavelets, the DWT, and signal decomposition, followed by an introduction to Benford's Law and its applications. The final part involves applying Benford’s Law to the DWT coefficients of different image genres, analyzing the results, and discussing further research.Applied Mathematic
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