Civil Engineering

Using ASTER images from Terra and a Digital Elevation Model (DEM) with its generated morphometric variables allowed the morphostructural mapping of the Toura range (Western Côte d’Ivoire). ASTER imagery enhancement procedures included principal components analysis, band ratios, data merging and spatial and directional filtering methods, which produced lithological and structural information that were combined with the morphometric analysis of the DEM. The characterization of the geological environment with VNIR and SWIR bands allowed the discrimination of the charnockitic rocks that intruded the gray gneisses, thanks to a change in tone and texture (body irregularities), along the contact area. For the morphostructural feature mapping, the SWIR ASTER bands particularly showed their capability for lineament extraction. The fracture network, identified and confirmed by earlier studies and field surveys, is distributed in the N 00-20°, N 60-80° and N 110°-120° directions. These intersect in several areas and form particular morphostructures that have trigonal and polygonal shapes. In the Eastern part, near the Sassandra major shear zone, the east-west faults are deviated by 60° to the south taking a 140-160° orientation. The joint use of ASTER images and the DEM as well as 3D representation improved the knowledge of the Toura range structural context, by completing faults inventory, especially in the north, where very few fractures were mapped in previous work.

Key-words : ASTER, DEM, mophostructural mapping, fracturing, Toura range, Côte d’Ivoire

Ce travail vise à simuler les écoulements dans les réservoirs fracturés du socle Archéen de Touba (Nord- Ouest de la Côte d’Ivoire). L’interprétation d’images satellitaires Landsat-TM est couplée aux investigations géologiques pour établir la carte de fracturation. Les caractéristiques géométriques du réseau de fractures, ainsi que l’analyse des lois d’échelles ont permis de construire le modèle de réseaux pertinents. La distribution en loi puissance des longueurs de fractures (distribution des ouvertures étant considérée uniforme) induit des écoulements fortement chenalisés suivant les axes de fracturation majeure. La perméabilité équivalente du réseau est comparée aux données hydrodynamiques existantes pour une validation du modèle géométrique ainsi que des paramètres hydrauliques. La concordance partielle entre les cheminements de l’eau et les forages à débits moyens et forts est un résultat prometteur dans la prospection des ressources en eau souterraine

A space time count process model is explained and applied to annual North Atlantic hurricane activity. The model uses the best-track data set of historical hurricane positions and intensities, together with climate variables, to determine local space time coefficients of a right-truncated Poisson process.

The truncated Poisson space time autoregressive (TPSTAR) model is motivated by first examining a time-series model for the entire domain. Then a Poisson generalized linear model is considered that uses grid boxes within the domain and adds offset factors for latitude and longitude. A natural extension is then made that includes instantaneous local and autoregressive coupling between the grids. A final version of the model is found by backward selection of the predictors based on values of Bayesian and Akiake information criteria. The final model has five nearest neighbours and statistically significant couplings. Hindcasts are performed on the hurricane seasons from 1994 to 1997.

Results show that, on average, model forecast probabilities are larger in regions in which hurricanes occurred. Quantitative skill assessment indicates some useful skill above climatology currently the default leading candidate. The TPSTAR model could be a valuable guidance product when issuing seasonal hurricane forecasts.

This study aims to apply the ultrasound technique in the
field of clean technology to protect environment. The principle
of ultrasound was conducted here to study the effect of applying
high frequency of ultrasound waves. Four kinds of water
namely; Seawater from Aqaba gulf, Red Sea, brackish from
Maan desert southern part of Jordan, hot spring from northern
part of Jordan and tap water (Amman City) were selected to
study the effect of ultrasound on its physical properties. High
ultrasound frequency device with 1.7 MHz was applied to
study the effect of ultrasound waves. All conducted experiments
were fixed at room temperature. The effect of liquid volume
while applying a constant ultrasound waves on the water properties
were investigated here. Exposing time of ultrasound
waves was fixed at 0.5, 1.0 and 1.5 h. The experimental
results showed that ultrasonic wave irradiation for different
samples of water at different period of time has its significant
impacts on physical and chemical properties of water such as
pH, total dissolved solids and consequently the conductivity.
Key Words: High frequency ultrasound, Total dissolved
solids, Water desalination, Water treatment, Environmental
protection, Physical properties.

Previous models of spinning disks have focused on modelling the disk as a spinning membrane. The effect of bending stiffness was then incorporated by adding the appropriate term to the previously derived spinning membrane equation. A pure spinning plate model does not exist in the literature. Furthermore, in both existing linear and nonlinear models of spinning disks, the in-plane inertia and rotary inertia of the disk have been ignored. This paper revisits the derivation of the equations of motion of a spinning plate. The derivation focuses on the use of Hamilton's principle with linear Kirchhoff and nonlinear von Karman strain expressions. In-plane and rotary inertias of the plate are automatically taken into account. The use of Hamilton's principle guarantees the correct derivation of the corresponding boundary conditions. The resulting equations and boundary conditions are discussed. © 2001 Elsevier Science Inc. All rights reserved.

In this paper, two recently derived linear models for the transverse vibrations of a spinning plate are considered. The disk is modelled as a pure plate with no membrane effects. Furthermore, the effect of the rotary inertia of the plate is taken into account. The first model is based on the assumption of linear (Kirchhoff) strains. The second model is based on the assumption of non-linear (von Karman) strains. The merits of both models are considered and their predictions are compared with those of the traditional linear model. © 2001 Elsevier Science Inc. All rights reserved.

A linear time-domain thermoelastic (photothermoacoustic) theory of a composite solid-liquid geometry has been developed. The theory includes multiple interreflections at all interfaces, acoustic diffraction and viscosity effects, and natural mixed, rigid, and free boundary conditions at the solid surface where laser-pulse incidence occurs (air-polystyrene interface). The theory was applied to experimental pressure-wave pulses from a Nd:YAG laser in a polystyrene well target and water system used for photomechanical drug delivery studies. Good fits of the linear theory to tripolar experimental pressure waveforms were possible at laser-pulse irradiances ≤100 MW/cm2, especially at distances ≤5 mm from the solid-fluid interface. It was further determined from the combined theoretical and experimental approach that the onset of significant hydrodynamic nonlinearity in the water appears for laser-pulse irradiances in the 165-MW/cm2 range, especially at axial distances z ∼ 8 mm, as expected theoretically from the laser-ablation-induced nonlinearity of stress-wave propagation in the solid-water system. © 2005 Optical Society of America.

This paper considers the dynamics of a spinning disk with the inclusion of in-plane inertia. The inclusion of the in-plane inertia couples the in-plane and transverse vibrations of the spinning disk. By considering one mode of each vibration, the problem can be reduced to a non-linear 2 DOF model. An analytical solution of this 2 DOF model is then developed using a time-averaged canonical perturbation approach and is compared with that of a numerical procedure. Through the use of these analytical and numerical tools, it becomes apparent that the inclusion of the in-plane inertia leads to the possibility of internal resonance between the oscillators, depending on the relationship between the natural frequencies of the two oscillators. © 2005 Elsevier Ltd. All rights reserved.

Surge flow irrigation can reduce the irrigation water losses and improve irrigation performance. In this study attempts have being made to design, manufacture and evaluate an automatic surge flow irrigation system. The system includes an automatic surge valve, which can be programmed by user based on field conditions such as soil infiltration characteristics changes during the irrigation season. The surge valve is inexpensive, portable and wireless and its energy is supplied by a chargeable battery, which the battery can also be recharged by a solar panel for a long duration uses. To evaluate the performance of the system, the surge valve including constant head water delivery system to the furrows were installed in an furrow irrigation experimental farm and based on input data given to the system the furrows were irrigated automatically by surge method with cycled inflow of 10 min on and 10 min off. The results showed that the system is able to accurately and automatically irrigate the furrows by surge method based on information given to the system. For the same discharge and volume of water applied to the furrows the water advance along the furrows were faster for surge flow as compared to the continuous flow.

This paper presents the results of an experimental investigation of the behaviour of T-end connections welded to rectangular hollow section (RHS) members subjected to axial tension. A total of 19 specimens were tested to failure. Parameters considered for the investigation were the tube size and the cap plate thickness. The cleat plate thickness was kept constant for all tests. The cleat plate orientation relative to the tube was investigated and was found to affect the joint strength. There was evidence of shear lag taking place. The test results also revealed that the use of very thick cap plates (more than 20 mm) does not lead to increased joint capacity. The yield line analysis was used to predict the failure loads and a comparison is made with the test results.

The word tensegrity is a contraction of tensional integrity. In simple structural terms, tensegrity systems are selfstressed pin-jointed networks. Each node receives at least one strut (compression member) and three cables (tension members). Tension members are thus prestressed against adjoining compression members. This is a pure form of tensegrity where only compression and tension members co-exist to form free-standing structures requiring minimum anchorage system compared with conventional types of structures. Double layer tensegrity systems are interesting because the compression members are relatively short, making the network quite rigid and compact. In the non-prestressed state, the system could be easily deployed. The present paper reviews limited research so far conducted at Coventry University on double layer tensegrity networks. It also reviews future directions in research into this fascinating field that has yet to be fully explored and exploited to find proper applications for it in the civil engineering discipline

The aim of the present paper is to review a novel modular constructional element for the building and construction industries that was patented by Coventry University. Modular elements have been used in the past in the construction of structures in order to speed construction and cut on time and cost. The modular element, the subject of this study, comprises hexagonal elements made of steel or other appropriate material, assembled together to form a constructional assembly of honeycomb form secured by fixings that clamp together the sides of adjacent elements. Concrete, or other appropriate material, is disposed within the elements providing a composite type of action. Reinforcement is also present in the form of bars or tubes, providing extra strength to the assembled element. The novel type of modular construction has potential applications in the building, construction, substructure and highways sectors. It could be used as a permanent or temporary structure for roofs and walls. It may also be used for concrete pavements, tunnelling, and retaining wall structures.

For this research focus on a study of the strength of concrete with ceramic waste as coarse aggregate and quarry dust as fine aggregate. The source of ceramic waste and quarry dust from the industrial in Malaysia. Nowadays, in ceramics industries production goes as waste, which is not recycling presently. In this study an attempt has been made to find the suitability of the ceramic industrial wastes and quarry dust as a possible substitution for conventional crushed stone coarse and fine aggregate. Experiment will carry out to determine the strength of concrete with ceramic waste coarse aggregate and quarry dust fine aggregate to compare them with the conventional concrete made (with crushed stone coarse aggregate and sand fine aggregate). The properties of the aggregate will also be compared.

This second part contains these chapters, in two files:

1 Chemistry: Reading Spectrograms
2 Performance Art: Problems of Documentation
3 Field Geology: Deductions from Beach Stones
4 Economics: Sirens in Classics, in Philosophy, and in Economic Theory
5 Linguistics: Medieval Irish Color Terms
6 Astrophysics: Doppler Tomography of Accretion Disks
7 Law: Video-game Technology in the Irish Bloody Sunday Tribunal
8 Computer Science: Visualizing the Internet
9 Occupational Therapy: Exercises in Doing, Being, and Becoming
10 Speech and Hearing Science: Speech Spectrograms
11 Restorative Dentistry: Matching Colours in Porcelain Crowns
12 Radio Astronomy: Observations of the Galactic Center
13 Archaeology: Imaging and Mapping Practices
14 Mapping: Uses of Geological Maps
15 Art History: Iconographic Analysis
16 Civil Engineering: A High Resolution Aerial Photograph

Originally published as Visual Practices Across the University, with contributions by thirty-five scholars (Munich: Wilhelm Fink Verlag, 2007).

1] We analyze inelastic off-fault response during earthquakes. Spontaneous crack-like rupture, with slip weakening, is modeled in 2-D plane strain using an explicit dynamic finite element procedure. A Mohr-Coulomb type elastic-plastic description describes the material bordering the fault. We identify the factors which control the extent and distribution of off-fault plasticity during dynamic rupture. Those include the angle with the fault of the maximum compressive prestress, the seismic S ratio, and the closeness of the initial stress state to Mohr-Coulomb failure. Plastic response can significantly alter the rupture propagation velocity, delaying or even preventing a transition to supershear rupture in some cases. Plastic straining also alters the residual stress field left near the fault. In part 1, we consider ''dry'' materials bordering the fault, or at least neglect pore pressure changes within them. Part 2 addresses the effects of fluid saturation, showing that analysis procedures of this part can describe undrained fluid-saturated response. Elastic-plastic laws of the type used are prone to shear localization, resulting in an inherent grid dependence in some numerical solutions. Nevertheless, we show that in the problems addressed, the overall sizes of plastic regions and the dynamics of rupture propagation seem little different from what are obtained when we increase the assumed plastic hardening modulus or dilatancy parameter above the theoretical threshold for localization, obtaining a locally smooth numerical solution at the grid scale. Evidence for scaling of some localization features with a real (nongrid) length scale in the model is also presented.

We develop a 2D slip-weakening description of a self-healing slip pulse that propagates dynamically in a steady-state configuration. The model is used to estimate patterns of off-fault secondary failure induced by the rupture, and also to infer fracture energies G for large earthquakes. This extends an analysis for a semiinfinite rupture to the case of a finite slipping zone length L of the pulse. The dynamic stress drop, when divided by the drop from peak to residual strength, determines the ratio of L to the slip-weakening zone length R. Predicted off-fault damage is controlled by that scaled stress drop, static and dynamic friction coefficients, rupture velocity, principal prestress orientation, and poroelastic Skempton coefficient. All damage zone lengths can be scaled by , which is proportional R* o G/(strength drop) 2 and is the value of R in the low-rupture-velocity, low-stress-drop, limit. In contrast to the Poliakov et al. (2002) case R/L ‫ס‬ 0, the region that supports Coulomb failure reaches a maximum size on the order of when mode II rupture R* o speed approaches the Rayleigh speed. Analysis of slip pulses documented by leads to estimates of G, each with a factor-of-two model uncertainty, from 0.1 to 9 MJ/m 2 (including the factor), averaging 2-4 MJ/m 2 ; G tends to increase with the amount of slip in the event. In most cases, secondary faulting should extend, at high rupture speeds, to distances from the principal fault surface on the order of 1 to 2 Ϸ 1-80 m for a 100-MPa strength drop; that distance should vary with depth, R* o being larger near the surface. We also discuss gouge and damage processes.

We analyze the observed dynamic slip transfer from the Denali to Totschunda faults during the M w 7.9 3 November 2002 Denali fault earthquake, Alaska. This study adopts the theory and methodology of and , in which it was shown that the propensity of the rupture path to follow a fault branch is determined by the preexisting stress state, branch angle, and incoming rupture velocity at the branch location. Here we check that theory on the Denali-Totschunda rupture process using 2D numerical simulations of processes in the vicinity of the branch junction. The maximum compression direction with respect to the strike of the Denali fault near the junction has been estimated to range from approximately 73Њ to 80Њ. We use the values of 70Њ and 80Њ in our numerical simulations. The rupture velocity at branching is not well constrained but has been estimated to average about 0.8 c s throughout the event. We use 0.6 c s , 0.8 c s , 0.9 c s , and even 1.4 c s as parameters in our simulations. We simulate slip transfer by a 2D elastodynamic boundary integral equation model of mode II slip-weakening rupture with self-chosen path along the branched fault system. All our simulations except for 70Њ and 0.9 c s predict that the rupture path branches off along the Totschunda fault without continuation along the Denali fault. In that exceptional case there is also continuation of rupture along the Denali fault at a speed slower than that along the Totschunda fault and with smaller slip. Dynamic Slip Transfer from the Denali to Totschunda Faults, Alaska: Testing Theory for Fault Branching

1] We consider a mode II rupture which propagates along a planar main fault and encounters an intersection with a branching fault. Using an elastodynamic boundary integral equation formulation, allowing the failure path to be dynamically self-chosen, we study the following questions: Does the rupture initiate along the branch? Does it continue? Is the extensional or compressional side most favored for branching? Does rupture continue on the main fault too? Failure is described by a slip-weakening law for which the strength at any amount of slip is proportional to normal stress. Our results show that dynamic stresses around the rupture tip, which increase with rupture velocity at locations off the main fault plane relative to those on it, could initiate rupture on a branching fault. As suggested by prior work, whether branched rupture can be continued to a larger scale depends on principal stress directions in the prestress state and on rupture velocity. The most favored side for branching rupture switches from the extensional to the compressional side as we consider progressively shallower angles of the direction of maximum compressive prestress with the main fault. Simultaneous rupturing on both faults can be activated when the branching angle is wide but is usually difficult for a narrow branching angle due to strong stress interactions between faults. However, it can be also be activated by enhanced dynamic stressing when the rupture velocity is very near the Rayleigh velocity. Natural examples seem consistent with the simulations that we present. INDEX TERMS: 7209 Seismology: Earthquake dynamics and mechanics; 7223 Seismology: Seismic hazard assessment and prediction; 7260 Seismology: Theory and modeling; 8010 Structural Geology: Fractures and faults; KEYWORDS: branching, fault, rupture propagation, boundary integral equation method (BIEM), fracture Citation: Kame, N., J. R. Rice, and R. Dmowska, Effects of prestress state and rupture velocity on dynamic fault branching,

AESTRACT CRACKS in ductile single crystals are analyzed here for geometries and orientations such that twodimensional states of anti-plane shear constitute possible deformation fields. The crystals are modelled as ideally plastic and yield according to critical resolved shear stresses on their slip systems. Restrictions on the asymptotic forms of stress and deformation fields at crack tips are established for anti-plane loading of stationary and quasistatically growing cracks, and solutions are presented for several specific orientations in f.c.c. and b.c.c. crystals. The asymptotic solutions are complemented by complete elastic-plastic solutions for stationary and growing cracks under small scale yielding, based on previous work by RICE (1967,1984) and FREUND (1979). Remarkably, the plastic zone at a stationary crack tip collapses into discrete planes of displacement and stress discontinuity emanating from the tip; plastic flow consists of concentrated shear on the displacement discontinuities.

†    Open architecture networks provide applications with fine-grained control over network elements. W ith this control comes the risk of misuse and new challenges to security beyond those present in conventional networks. One particular security requirement is the ability of applications to protect the secrecy and integrity of transmitted data while sti ll allowing trusted active elements within the network to opera te on that data. This paper describes mechanisms for identifying tru sted nodes within a network and securely deploying adapt ation instructions to those nodes while protecting applic ation data from unauthorized access and modification. Promisi ng experimental results of our implementation within t he Conductor adaptation framework will also be present ed, suggesting that such features can be incorporated i nto real networks.

WE CONSIDER quasistatic motion and stability of a single degree of freedom elastic system undergoing frictional slip. The system is represented by a block (slider) slipping at speed V and connected by a spring of stillness k to a point at which motion is enforced at speed V,. We adopt rate and state dependent frictional constitutive relations for the slider which describe approximately experimental results of Dieterich and Ruina over a range of slip speeds % In the simplest relation the friction stress depends additively on a term A In V and a state variable 0; the state variable B evolves, with a characteristic slip distance, to the value -B In K where the constants A, Bare assumed to satisfy B > A > 0. Limited results are presented based on a similar friction Iaw using two state variables.

ANALYSIS of the deformation field consistent with a Prandtl stress distribution travelling with an advancing plane-strain crack reveals the functional form of the near tip crack profile in an elastic-plastic solid. The crack opening 6 is shown to have the form 6 N r In (const./r) at a distance r from the tip. This observation coupled with data generated from finite element investigations of growing cracks in small-scale yielding permits the construction of a relation characterizing the deformation at an extending crack tip. A ductile crack-growth criterion consisting of the attainment of a critical opening at a small characteristic material distance from the tip is adopted. Predictions of the stability of a growing crack for both small-scale yielding specimens and those subject to general yielding are discussed.

Recent finite-element results by S. Cl. Larsson and A. J. Carlsson suggest a limited range of validity to the 'small scale yielding approximation', whereby small crack tip plastic zones are correlated in terms of the elastic stress intensity factor, It is shown with the help of a model for plane strain yielding that their results may be explained by considering the non-singular stress, acting parallel to the crack at its tip, which accompanies the inverse square-root elastic singularity. Further implications of the non-singular stress term for crack tip deformations and fracturing are examined. It is suggested that its effect on crack tip parameters, such as the opening displacement and J-integral, is less pronounced than its effect on the yield zone size.

We investigate the problem of monotonicity reconstruction, as defined in , in a distributed setting. We have oracle access to a nonnegative real-valued function f defined on domain [n] d = {1, . . . , n} d . We would like to closely approximate f by a monotone function g. This should be done by a procedure (a filter) that given as input a point x ∈ [n] d outputs the value of g(x), and runs in time that is highly sublinear in n. The procedure can (indeed must) be randomized, but we require that all of the randomness be specified in advance by a single short random seed. We construct such an implementation where the time and space per query is (log n) O(1) and the size of the seed is polynomial in log n and d. Furthermore the distance of the approximating function g from f is at most a constant multiple of the minimum distance of any monotone function from f . This allows for a distributed implementation: one can initialize many copies of the filter with the same short random seed, and they can autonomously handle queries, while producing outputs that are consistent with the same approximating function g.

A valid approach for the limit analysis of existing masonry buildings in seismic areas concerns the application of single or combined kinematic models involving the equilibrium of structural macro-elements. These can be more reliable in describing the real structural behaviour than common equivalent static procedures, based on the “box” behaviour of the structure and on the elasto-plastic behaviour of the masonry. Based on the results presented in Part 1, which provided a critical review of the reliability of the structural models and of the effectiveness of the repair techniques applied in the past decades, analytical procedures able to interpreter the mechanisms included in the abacus of typical damage are proposed. The main results of the vulnerability analyses carried out on urban centres characterized by different typologies of buildings, suffering different levels of damage, are discussed. Structural assessment is also performed, by simulating intervention proposals in order to evaluate the seismic improvement.

A methodology of investigation and diagnosis of the built heritage of historic centres in seismic areas of Italy is proposed. The aim is to collect an extensive knowledge on the structural typologies and behaviour of historic masonry buildings for the prevention and/or repair of damages caused by earthquakes. Small historic centres or residential buildings in larger centres have been for long time considered as “minor architecture”, but they are meaningful testimonies of the Italian cultural heritage. The results of the investigation also allowed a critical review of the reliability of the analytical models and of the effectiveness of the repair techniques applied in the past decades. The guidelines emerging from the results of an extensive research are presented in this paper (Part 1 of the study). A "minimal" investigation program, which can support the designers in their projects and appropriate mathematical models to study the vulnerability of the structures is suggested.

This paper presents an axiomatic model of medical decision making and discusses its potential applications. The medical decision problems envisioned concern the choice of a medical treatment following a diagnosis in situations in which data allow construction of an empirical distribution over the potential outcomes associated with the alternative treatments. In its descriptive interpretation, the model is an hypothesis about the patient's choice behavior. The theory also aims to aid physicians recommend treatments in a coherent manner. * I benefited from comments of Ani

In 1994, Witkin and Heckbert developed a method for interactively modeling implicit surfaces by simultaneously constaining a particle system to lie on an implicit surface and vice-versa. This interface was demonstrated to be effective and easy to use on example models containing a few blobby spheres and cylinders. This system becomes much more difficult to implement and operate on more complex implicit models. The derivatives needed for the particle system behavior can become laborious and error-prone when implemented for more complex models. We have developed, implemented and tested techniques for automatic and numerical differentiation of the implicit surface function. Complex models also require a large number of parameters, and the management and control of these parameters is often not intuitive. We have developed adapters, which are special shape-transformation operators that automatically adjust the underlying parameters to yield the same effect as the transformation. These new techniques allow constrained particle systems to sample and control more complex models than before possible.

Each tree is unique because of the physical environment it experiences over the course of its life. Environmental factors shape a tree within the bounds of its genotype. Only by modeling the environmental influences can we create realistic models of trees. To this end, we constructed a structural simulation that calculates the mass of each branch of the tree to emulate the mechanisms the tree uses to balance its weight, and that estimates the photosynthesis return of the leaves to simulate phototropism. Our effort is motivated by a desire to construct a predictive tool that can be used by both those in computer graphics and forest management, with applications in image synthesis, dendrochronology, mensuration and the simulation of forest succession.

Among the basic equations one might wish a computer to solve s y m bolically is the inverse of the power function, solving y = z w for z. While many special cases, easily solved, abound, the general question is fraught with implications: if this is so hard, how can we expect success in other ventures? Having solved this, we can naturally use it in a \composition" of solution methods for expressions of the form y = f (z) w .

Replacing parametrization of a domain with polyhedral approximations we give an optimal extension of the Divergence Theorem. Permitted domains of integration, called chainlets, range from smooth submanifolds to structures that may not be locally Euclidean and have no tangent vectors defined anywhere. One may still calculate divergence over the domain, and flux through its boundary which itself may have no normal vectors defined anywhere.

We present here the fundamentals of a theory of domains that offers unifying techniques and terminology for a number of different fields. Using direct, geometric methods, we develop integration over pdimensional domains in n-dimensional Euclidean space R n , replacing the method of parametrization of a domain with the method of approximation in Banach spaces. We prove basic results needed for a theory of integration -continuity of the integral as a function of its domain and integrand (Corollary 4.6) and a generalization of Stokes' theorem (Corollary 4.12). * Note that the spaces B r,α are defined for (r, α) ≥ 0 while the spaces A r,α are defined for (r, α) > −1. In the sequel [H2] we prove that dual spaces of co-chainlets correspond to spaces of differential forms. Almgren [A] proved that mass continuous cochains correspond to forms, but these are not necessarily measurable. The Banach spaces A −1,α are used to define the spaces A α , beginning an induction process.

This paper proves an isomorphism theorem for cochains and differential forms, before passing to cohomology. De Rham's theorem is a consequence. This leads to an extension of much of calculus and homology theory to nonsmooth domains, called chainlets and makes available combinatorial techniques for smooth domains that limit to the classic analytic methods. We find maximal subspaces of L 1 forms that satisfy Stokes' theorem for domains of chainlets giving a measurable, as well as optimal, extension of the theory. * This duality is not present in the C ∞ Seifert counterexamples of Kuperberg [K].

A soap film is actually a thin solid fluid bounded by two surfaces of opposite orientation. It is natural to model the film using one polyhedron for each side. Two problems are to get the polyhedra for both sides to be in the same place without canceling each other out and to model triple junctions without introducing extra boundary components. We use chainlet geometry to create dipole cells and mass cells which accomplish these goals and model faithfully all observable soap films and bubbles. We introduce a new norm on chains of these cells and prove lower semicontinuity of area. A geometric version of Cartan's magic formula provides the necessary boundary coherence.

In this paper we propose to jointly detect lane and pavement boundaries by fusing information from both optical and radar images acquired with the sensor system mounted on the top of the host vehicle. The boundaries are described with concentric circular models. The optical and radar imaging processes are modeled as Gaussian and log-normal probability densities. The multisensor fusion boundary detection problem is posed in a Bayesian framework and a maximum a posteriori (MAP) estimate is employed to locate the lane and pavement boundaries. Since the circular model parameters possess compatible units and are in the same order of magnitude, the estimation problem is much better conditioned than using the previous parabolic models, whose parameters are incompatible with each other. This fusion algorithm achieves analytical integration of two different sensing modalities due to the validation of the likelihoods that describe both optical and radar imaging processes. Experimental results have shown that the fusion algorithm outperforms single sensor based boundary detection algorithms in a variety of road scenarios.

An apology is an explanation or defense of actions which may otherwise be misunderstood. There are several sources of misunderstanding concerning the proof of the Riemann hypothesis. An obstacle lies in the narrow perception of the Riemann hypothesis as a mechanism for counting prime numbers. The Riemann hypothesis is significant because of its significance in mathematical analysis. The proof cannot be read as an isolated argument because of its roots in the history of mathematics. Another obstacle lies in the unexpected source of the proof of the Riemann hypothesis. The proof is made possible by events which seem at first sight to have no relevance to mathematics. Exceptional people and exceptional circumstances prepared the proof of the Riemann hypothesis.

In the symmetric rendezvous search game played on K n (the completely connected graph on n vertices) two players are initially placed at two distinct vertices (called locations). The game is played in discrete steps and at each step each player can either stay where he is or move to a different location. The players share no common labelling of the locations. They wish to minimize the expected number of steps until they first meet. Rendezvous search games of this type were first proposed by Steve Alpern in 1976. They are simple to describe, and have received considerable attention in the popular press as they model problems that are familiar in real life. They are notoriously difficult to analyse. Our solution of the symmetric rendezvous game on K 3 makes this the first interesting game of its type to be solved, and establishes the long-standing conjecture that the Anderson-Weber strategy is optimal.

A notion of curvature is introduced in multivariable operator theory. The curvature invariant of a Hilbert module over [z 1 z d ] is a nonnegative real number which has significant extremal properties, which tends to be an integer, and which is hard to compute directly. It is shown that for graded Hilbert modules, the curvature agrees with the Euler characteristic of a certain finitely generated algebraic module over the appropriate polynomial ring. This result is a higher dimensional operator-theoretic counterpart of the Gauss-Bonnet formula which expresses the average Gaussian curvature of a compact oriented Riemann surface as the alternating sum of the Betti numbers of the surface, and it solves the problem of calculating the curvature of graded Hilbert modules. The proof of that result is based on an asymptotic formula which expresses the curvature of a Hilbert module in terms that allow its comparison to a corresponding asymptotic expression for the Euler characteristic.

The behavior of steel-concrete composite beams is strongly influenced by the type of shear connection between the steel beam and the concrete slab. For accurate analytical predictions, the structural model must account for the interlayer slip between these two components. In numerous engineering applications ͑e.g., in the fields of structural optimization, structural reliability analysis, and finite element model updating͒, accurate response sensitivity calculations are needed as much as the corresponding response simulation results. This paper focuses on a procedure for response sensitivity analysis of steel-concrete composite structures using displacement-based locking-free frame elements including deformable shear connection with fiber discretization of the cross section. Realistic cyclic uniaxial constitutive laws are adopted for the steel and concrete materials as well as for the shear connection. The finite element response sensitivity analysis is performed according to the direct differentiation method. The concrete and shear connection material models as well as the static condensation procedure at the element level are extended for response sensitivity computations. Two steel-concrete composite structures for which experimental test results are available in the literature are used as realistic testbeds for response and response sensitivity analysis. These benchmark structures consist of a nonsymmetric, two-span continuous beam subjected to monotonic loading and a frame subassemblage under cyclic loading. The new analytical derivations for response sensitivity calculations and their computer implementation are validated through forward finite difference analysis based on the two benchmark examples considered. Selected sensitivity analysis results are shown for validation purposes and for quantifying the effect and relative importance of the various material parameters in regards to the nonlinear monotonic and cyclic response of the testbed structures.

In New York City, in the United States as a whole, and in the rest of the world, there are many projects with high-performance features and environmental ambitions already completed or being built. Unfortunately, few projects are consistently followed-up and evaluated, which means that valuable information is lost.  For this reason, this research attempts to gather information from high-performance building projects in order to analyze and understand the impacts (e.g., both positive and negative) of adopting the Leadership in Energy and Environmental Design (LEED) standards as the criteria of public buildings being planned and/or renovated. The focus of this thesis is to identify the financial costs and benefits of high-performance building design prescribed by the proposed law Int. No. 0324-2004 in New York City, U.S. The discussion in this study is based on how the public projects will be affected if the bill is passed by the City Council. The aim is to deliver information for the early stages of new building projects.  The analysis results are described in terms of the savings, payback time, and the process behind of project realization. The bill’s scenario has been analyzed and evaluated using methods such as life-cycle costing, net present value, and cost-benefit analysis. It is important to state that the impacts referred to by this thesis are divided into internal influence (i.e., running costs and maintenance) and the external influence (i.e., the public savings of reducing the water treatment costs).

Keywords: Environmental design, design strategies, Int. No. 324, financial benefits, Leadership on Energy and Environmental Design, LEED, high-performance buildings, New York City.

The dynamics of slender filaments or fibers suspended in Stokesian fluids are fundamental to understanding many flows arising in physics, biology and engineering. Such filaments can have aspect ratios of length to radius ranging from a few tens to several thousands. Full discretizations of such 3D flows are very costly. Instead, we employ a non-local slender body theory that yields an integral equation, along the filament centerline, relating the force exerted on the body to the filament velocity. This hydrodynamical description takes into account the effect of the filament on the fluid, and is extended to capture the interaction of multiple filaments as mediated by the intervening fluid. We consider filaments that are inextensible and elastic. Replacing the force in the slender body integral equation by an explicit expression that uses Euler-Bernoulli theory to model bending and tensile forces yields an integral expression for the velocity of the filament centerlines, coupled to auxiliary integro-differential equations for the filament tensions. Based on a regularized version of these slender body equations that is asymptotically equivalent to the original formulation, we construct a numerical method which uses a combination of finite differences, implicit time-stepping to avoid severe stability constraints, and special quadrature methods for nearly singular integrals. We present simulations of single flexible filaments, as well as multiple interacting filaments, evolving in a background shear flow. These simulations show shear induced buckling and relaxation of the filaments, leading to the storage and release of elastic energy. These dynamics are responsible for the development of positive first normal stress differences, commonly associated with visco-elastic fluids that are suspensions of microscopic elastic fibers.

Animation through the numerical simulation of physicsbased graphics models offers unsurpassed realism, but it can be computationally demanding. Likewise, the search for controllers that enable physics-based models to produce desired animations usually entails formidable computational cost. This paper demonstrates the possibility of replacing the numerical simulation and control of dynamic models with a dramatically more efficient alternative. In particular, we propose the NeuroAnimator, a novel approach to creating physically realistic animation that exploits neural networks. NeuroAnimators are automatically trained off-line to emulate physical dynamics through the observation of physicsbased models in action. Depending on the model, its neural network emulator can yield physically realistic animation one or two orders of magnitude faster than conventional numerical simulation. Furthermore, by exploiting the network structure of the NeuroAnimator, we introduce a fast algorithm for learning controllers that enables either physics-based models or their neural network emulators to synthesize motions satisfying prescribed animation goals. We demonstrate NeuroAnimators for a variety of physics-based models.

Highways are an essential component of our society because they are critical to quality of life and to local and national economies. Under good conditions, highways provide a safe and efficient route for people and goods to reach their destinations. However, as a direct consequence of their use, traffic congestion is ever-increasing, undermining the ability of highways to adequately provide an acceptable quality of service. It has become imperative for highway traffic to provide the same time guarantee quality as other transportation methods such as air and rail travel, while maintaining the convenience of flexible scheduling and destination for the individual traveler.

The only way to keep up with the ever-increasing number of cars on roads is through constant change and improvement in the transportation infrastructure. Construction of new roads is constrained by space and financial resources. Therefore, there is a need to devise ways to make optimal use of the existing infrastructure. In this position paper, we describe a lane reservation system for highways. The idea is to allow drivers to reserve a slot on a high-priority lane by paying a premium price. The high-priority lane would provide congestion free travel between any two points on the highway. We describe the design of our system, the challenges that need to be solved and the evaluation methodology we are planning to adopt.

VANETs (vehicular ad hoc networks) are emerging as a new network environment for intelligent transportation systems. Many of the applications built for VANETs will depend on the data push communication model, where information is disseminated to a group of vehicles. In this paper, we present a formal model of data dissemination in VANETs and study how VANET characteristics, specifically the bidirectional mobility on well defined paths, affects the performance of data dissemination. We study the data push model in the context of TrafficView, a system we have implemented to disseminate information about the vehicles on the road. Traffic data could be disseminated using vehicles moving on the same direction, vehicles moving in the opposite direction, or vehicles moving in both directions. Our analysis as well as simulation results show that dissemination using only vehicles in the opposite direction increases the data dissemination performance significantly.