Infrastructure dynamics: A selected bibliography

The term infrastructure is used to denote the set of life support and public service systems which is necessary for the development of growth of human settlements. Included are some basic references in the field of dynamic simulation, as well as a number of relevant applications in the area of infrastructure planning. The intent is to enable the student or researcher to quickly identify such applications to the extent necessary for initiating further work in the field

The mean ratio set for ax+b valued cocycles

Let X = Q 1 i=1 Z `(i) be acted upon by the group Q i=1 `(i) i=1 `(i) of changes in nitely many coordinates and a G-measure on X which is nonsingular for the ax+b group. We give a structure theorem for such cocycles, we dene the mean ratio set which is a closed subgroup of the ax + b group and we exhibit for each closed subgroup a cocycle whose mean ratio set is the given subgroup

A study of the manuscript Lawāmi‘ al-anwār al-qulūb, by Shaydhala (12th century): author, methodology and investigation strategies

هذه الدراسة تركز على تحليل مخطوطة "لوامع أنوار القلوب فى جوامع أسرار المحب والمحبوب" للفقيه الشافعي أبو المعالى عزيزي بن عبد الملك بن منصور الجيلي، المعروف بشَيذَلَة (القرن الثانى عشر الميلادى). هذه المخطوطة غير المنشورة والتى تتكون من عشرة فصول يجب تصنيفها فى الأدب العربى فى العصور الوسطى ضمن كتب الصوفية,فبعد دراسة البنية الداخلية للمخطوطة ,والترجمة للمؤلف وظروف حياته والتعرف على أسلوبه؛ تبيَّن أنَّ هذا العمل يركز بشكل أساسي على اللغة والمصطلحات والموضوعات والعناصر والسمات الممي زة لهذا النوع من الجنس الأدبى القاصد لوصف الحب الإلهي ,ومن بين هذه المسائل وغيرها؛ نستنتج أ ن هذه المخطوطة تُش كل حلقةً أخرى فى سلسلة كتب الأدب الصوفي الذى يقود إلى معانى الرقة المفرطة ,والمتعة,والمؤانسة,والنورانية ,والتقارب بين المرء وخالقه.Este estudio se centra en el análisis del manuscrito Lawāmi‘ al-anwār al-qulūb fī ŷawāmi‘ asrār al-muḥibb wa-l-maḥbūb (El brillo de las luces de los corazones en en el conjunto de los secretos del amante y el amado), del jurista šafi‘ī Abū l-Ma‘ālī ‘Azīzī b. ‘Abd al-Malik b. Manṣūr al-Ŷīlī, conocido como Šaydala (s. XII). Se trata de una obra inédita, de diez capítulos, que debe ser clasificada entre los libros de sufismo de la literatu-ra árabe medieval. Tras estudiar la estructura interna del manuscrito, al autor y su contexto, este trabajo se centra principalmente en el lenguaje, la terminología, los temas y los ele-mentos característicos de este tipo de género literario destinado a describir el amor divino. Entre otras cuestiones, se llega a la conclusión de que este manuscrito constituye un esla-bón más de la serie de libros de literatura sufí que apuntan al refinamiento, disfrute, socia-bilidad, iluminación y convergencia entre el hombre y su creador.This study analyzes the manuscript Lawāmi‘ al-anwār al-qulūb fī jawāmi‘ asrār al-muḥibb wa-l-maḥbūb (The brilliance of the lights of hearts in the series of secrets known by the lover and the beloved), by the jurist shafi‘ī Abū l-Ma‘ālī ‘Azīzī b. ‘Abd al-Malik b. Manṣūr al-Jīlī, known as Shaydhala (12th century). The manuscript is of an un-published work of ten chapters that must be classified alongside the Sufism books of me-dieval Arabic literature. After studying the work's internal structure, author and context, attention is given to the language, terminology, themes and the elements characteristic of this literary genre, the purpose of which was to describe divine love. Among other ques-tions, the paper reaches the conclusion that this manuscript represents yet another link in the series of books in Sufi literature that point to the refinement, enjoyment, sociability, enlightenment and convergence between man and his creator

Nonhyperbolic reflection moveout for orthorhombic media

Reflection moveout in azimuthally anisotropic media is not only azimuthally dependent but it is also nonhyperbolic. As a result, the conventional hyperbolic normal moveout (NMO) equation parameterized by the exact NMO (stacking) velocity loses accuracy with increasing offset (i.e., spreadlength). This is true even for a single-homogeneous azimuthally anisotropic layer. The most common azimuthally anisotropic models used to describe fractured media are the horizontal transverse isotropy (HTI) and the orthorhombic (ORT). Here, we introduce an analytic representation for the quartic coefficient of the Taylor’s series expansion of the two-way traveltime for pure mode reflection (i.e., no conversion) in arbitrary anisotropic media with arbitrary strength of anisotropy. In addition, we present an analytic expression for the long-spread (large-offset) nonhyperbolic reflection moveout (NHMO). In this study, special attention is given to Pwave propagation in orthorhombic media with horizontal interfaces. The quartic coefficient, in general, has a relatively simple form, especially for shear wave propagation. The reflection moveout for each shear-wave mode in a homogeneous orthorhombic medium is purely hyperbolic in the direction normal to the polarization. In addition, the nonhyperbolic portion of the moveout for shear-wave propagation reaches its maximum along the polarization direction, and it decreases rapidly away from the direction of polarization. Hence, the anisotropy-induced nonhyperbolic reflection moveout for shear-wave propagation is significant in the vicinity of the polarization directions. In multilayered azimuthally anisotropic media, the NMO (stacking) velocity and the quartic moveout coefficient can be calculated with good accuracy using Dix-type averaging (e.g., the known averaging equations for VTI media). The interval NMO velocities and the interval quartic coefficients, however, are azimuthally dependent. This allows us to extend the nonhyperbolic moveout (NHMO) equation, originally designed for VTI media, to more general horizontally stratified azimuthally anisotropic media. Numerical examples from reflection moveout in orthorhombic media, the focus of this paper, show that this NHMO equation accurately describes the azimuthally-dependent P-wave reflection traveltimes, even on spreadlengths twice as large as the reflector depth. This work provides analytic insight into the behavior of nonhyperbolic moveout, and it has important applications in modeling and inversion of reflection moveout in azimuthally anisotropic media.Massachusetts Institute of Technology. Earth Resources LaboratorySaudi Aramc

Evaluation of the Pulmonary Veins and Left Atrial Volume using Multidetector Computed Tomography in Patients Undergoing Catheter Ablation for Atrial Fibrillation

Catheter ablation is an evolving treatment option in patients with atrial fibrillation. Contrast enhanced electrocardiogram-gated multi-detector computed tomography (MDCT) has rapidly evolved over the past few years into an important tool in the diagnosis of coronary atherosclerosis. There is increasing recognition that MDCT is a useful tool to evaluate non-coronary structures, such as cardiac chambers, valves, the coronary sinus and adjacent structures including pulmonary veins. In particular, MDCT is playing an increasingly important role in the evaluation of the left atrium and the pulmonary veins in patients undergoing catheter ablation for atrial fibrillation. It provides accurate and reliable identification of the pulmonary veins and anatomical relationship between the left atrium and esophagus although the mobile esophagus may limit the value of MDCT to reduce the risk of atrio-esophagus fistula. In this article, we will review the evaluation of the left atrium and pulmonary veins using MDCT in patients undergoing catheter ablation of atrial fibrillation

Combinatorics of linear iterated function systems with overlaps

Let $\bm p_0,...,\bm p_{m-1}$ be points in ${\mathbb R}^d$, and let $\{f_j\}_{j=0}^{m-1}$ be a one-parameter family of similitudes of ${\mathbb R}^d$: $$f_j(\bm x) = \lambda\bm x + (1-\lambda)\bm p_j, j=0,...,m-1,$$ where $\lambda\in(0,1)$ is our parameter. Then, as is well known, there exists a unique self-similar attractor $S_\lambda$ satisfying $S_\lambda=\bigcup_{j=0}^{m-1} f_j(S_\lambda)$. Each $\bm x\in S_\lambda$ has at least one address $(i_1,i_2,...)\in\prod_1^\infty\{0,1,...,m-1\}$, i.e., $\lim_n f_{i_1}f_{i_2}... f_{i_n}({\bf 0})=\bm x$. We show that for $\lambda$ sufficiently close to 1, each $\bm x\in S_\lambda\setminus\{\bm p_0,...,\bm p_{m-1}\}$ has $2^{\aleph_0}$ different addresses. If $\lambda$ is not too close to 1, then we can still have an overlap, but there exist $\bm x$'s which have a unique address. However, we prove that almost every $\bm x\in S_\lambda$ has $2^{\aleph_0}$ addresses, provided $S_\lambda$ contains no holes and at least one proper overlap. We apply these results to the case of expansions with deleted digits. Furthermore, we give sharp sufficient conditions for the Open Set Condition to fail and for the attractor to have no holes. These results are generalisations of the corresponding one-dimensional results, however most proofs are different.Comment: Accepted for publication in Nonlinearit

Bis(2,6-diamino­pyridin-1-ium) hexa­aqua­cobalt(II) disulfate dihydrate

In the title compound, (C5H8N3)2[Co(H2O)6](SO4)2·2H2O, the complete complex cation is generated by crystallographic inversion symmetry, such that the CoII cation is octa­hedrally coordinated by six water mol­ecules. The organic cation is essentially planar, with a maximum deviation of 0.013 (1) Å. In the crystal structure, the ions and mol­ecules are linked into a pseudo-layered three-dimensional supra­molecular network via O—H⋯O and N—H⋯O hydrogen bonds. Weak inter­molecular π–π inter­actions further stabilize the crystal structure [centroid–centroid distance = 3.5231 (4) Å]

Estudio del manuscrito Lawāmi‘ al-anwār al-qulūb de Šaydala (s. XII): el autor, la metodología y las estrategias de investigación

This study analyzes the manuscript Lawāmi‘ al-anwār al-qulūb fī jawāmi‘ asrār al-muḥibb wa-l-maḥbūb (The brilliance of the lights of hearts in the series of secrets known by the lover and the beloved), by the jurist shafi‘ī Abū l-Ma‘ālī ‘Azīzī b. ‘Abd al- Malik b. Manṣūr al-Jīlī, known as Shaydhala (12th century). The manuscript is of an un- published work of ten chapters that must be classified alongside the Sufism books of me- dieval Arabic literature. After studying the work's internal structure, author and context, attention is given to the language, terminology, themes and the elements characteristic of this literary genre, the purpose of which was to describe divine love. Among other ques- tions, the paper reaches the conclusion that this manuscript represents yet another link in the series of books in Sufi literature that point to the refinement, enjoyment, sociability, enlightenment and convergence between man and his creator.Este estudio se centra en el análisis del manuscrito Lawāmi‘ al-anwār al-qulūb fī ŷawāmi‘ asrār al-muḥibb wa-l-maḥbūb (El brillo de las luces de los corazones en en el conjunto de los secretos del amante y el amado), del jurista šafi‘ī Abū l-Ma‘ālī ‘Azīzī b. ‘Abd al-Malik b. Manṣūr al-Ŷīlī, conocido como Šaydala (s. XII). Se trata de una obra inédita, de diez capítulos, que debe ser clasificada entre los libros de sufismo de la literatu- ra árabe medieval. Tras estudiar la estructura interna del manuscrito, al autor y su contexto, este trabajo se centra principalmente en el lenguaje, la terminología, los temas y los ele- mentos característicos de este tipo de género literario destinado a describir el amor divino. Entre otras cuestiones, se llega a la conclusión de que este manuscrito constituye un esla- bón más de la serie de libros de literatura sufí que apuntan al refinamiento, disfrute, sociabilidad, iluminación y convergencia entre el hombre y su creador

Multifractal properties of tribonacci chains

We introduce two one-dimensional tight-binding models based on the tribonacci substitution—the hopping and on-site tribonacci chains—which generalize the Fibonacci chain. For both hopping and on-site models, a perturbative real-space renormalization procedure is developed. We show that the two models are equivalent at the fixed point of the renormalization-group flow, and that the renormalization procedure naturally gives the local resonator modes. Additionally, the Rauzy fractal, inherent to the tribonacci substitution, is shown to serve as the analog of conumbering for the tribonacci chain. The renormalization procedure is used to repeatedly subdivide the Rauzy fractal into copies of itself, which can be used to describe the eigenstates in terms of local resonator modes. Finally, the multifractal dimensions of the energy spectrum and eigenstates of the hopping tribonacci chain are computed, from which it can be concluded that the tribonacci chains are critical