Academic literature on the topic 'Limit shapes'
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Journal articles on the topic "Limit shapes"
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DeSALVO, STEPHEN, and IGOR PAK. "Limit Shapes via Bijections." Combinatorics, Probability and Computing 28, no. 2 (2018): 187–240. http://dx.doi.org/10.1017/s0963548318000330.
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We compute the limit shape for several classes of restricted integer partitions, where the restrictions are placed on the part sizes rather than the multiplicities. Our approach utilizes certain classes of bijections which map limit shapes continuously in the plane. We start with bijections outlined in [43], and extend them to include limit shapes with different scaling functions.
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Pepelnjak, T., and B. Barisic. "Computer-assisted engineering determination of the formability limit for thin sheet metals by a modified Marciniak method." Journal of Strain Analysis for Engineering Design 44, no. 6 (2009): 459–72. http://dx.doi.org/10.1243/03093247jsa503.
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Development of a new sheet-metal-forming technology in a digital environment demands accurate and reliable mechanical properties and forming limits of the selected material. It is essential to determine the forming limits for thin sheets and foils. Implementation of the Marciniak procedure with strip-shaped specimens defining the left-hand side of the forming limit diagram (FLD) results in tearing outside the observed area of the specimen. Therefore, new shapes of test pieces were designed with a strip-shaped central area and enlarged outer areas, which were in contact with the die during the forming process. The radius of the specimen enlargement enabled a co-axial contact of its edge and direction of the material flow over the die radius during the forming process. The shape of the redesigned geometry of the specimen was analysed using the finite element (FE) program ABAQUS to minimize undesired stress concentrations at the die radius. Finally, strain paths variations due to shape change were analysed. The new specimen concept was verified on TS-275 tinplate steel with a thickness of 0.24 mm. By implementing the necessary redesigned specimen shapes and by analysis of the tearing limit of the TS-275 material, the forming limit curve for the tinplate material under investigation was constructed.
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Okounkov, Andrei. "Limit shapes, real and imagined." Bulletin of the American Mathematical Society 53, no. 2 (2015): 187–216. http://dx.doi.org/10.1090/bull/1512.
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Bocini, Saverio, and Jean-Marie Stéphan. "Non-probabilistic fermionic limit shapes." Journal of Statistical Mechanics: Theory and Experiment 2021, no. 1 (2021): 013204. http://dx.doi.org/10.1088/1742-5468/abcd34.
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Johansson, Kurt. "Edge fluctuations of limit shapes." Current Developments in Mathematics 2016, no. 1 (2016): 47–110. http://dx.doi.org/10.4310/cdm.2016.v2016.n1.a2.
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Vassiliev, Nikolai, Vasilii Duzhin, and Artem Kuzmin. "Modeling of bumping routes in the RSK algorithm and analysis of their approach to limit shapes." Information and Control Systems, no. 6 (December 27, 2022): 2–9. http://dx.doi.org/10.31799/1684-8853-2022-6-2-9.
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Introduction: The RSK algorithm establishes an equivalence of finite sequences of elements of linearly ordered sets and pairs of Young tableaux P and Q of the same shape. Of particular interest is the study of the asymptotic limit, i. e., the limit shape of the so-called bumping routes formed by the boxes of tableau P affected in a single iteration of the RSK algorithm. The exact formulae for these limit shapes were obtained by D. Romik and P. Śniady in 2016. However, the problem of investigating the dynamics of the approach of bumping routes to their limit shapes remains insufficiently studied. Purpose: To study the dynamics of distances between the bumping routes and their limit shapes in Young tableaux with the help of computer experiments. Results: We have obtained a large number of experimental bumping routes through a series of computer experiments for Young tableaux P of sizes up to 4·106, filled with real numbers in the range [0, 1] and sets of inserted values α Î [0.1, 0.15, … , 0.85]. We have compared these bumping routes in the L2 metric with the corresponding limit shapes and have calculated the average distances and variances of their deviations from the limit shapes. We present an empirical formula for the rate of approach of discretized bumping routes to their limit shapes. Also, the experimental parameters of the normal distributions of the deviations of the bumping routes are obtained for various input values.
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Jeswiet, J., and D. Young. "Forming limit diagrams for single-point incremental forming of aluminium sheet." Proceedings of the Institution of Mechanical Engineers, Part B: Journal of Engineering Manufacture 219, no. 4 (2005): 359–64. http://dx.doi.org/10.1243/095440505x32210.
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The single-point incremental forming (SPIF) process is described. The maximum draw angle for SPIF is defined and specific values are given for 3003-0 and 5754-0 aluminium. Forming limit diagrams (FLDs) are developed for incremental forming of aluminium sheet, using SPIF. Five distinct shapes are used to define the forming limits: a hemisphere, a straight-sided cone, a hyperbolic-sided cone, a pyramid, and a shape with five lobes. Strains of more than 300 per cent have been achieved for all shapes.
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Bobek, Jiří, Jiří Šafka, Martin Seidl, and Jiří Habr. "Mechanical Properties of Metal-Plastic Composite with Internal Fractal Shape Reinforcing Structure." Defect and Diffusion Forum 368 (July 2016): 170–73. http://dx.doi.org/10.4028/www.scientific.net/ddf.368.170.
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This paper deals with mechanical properties research of innovative polymer multiphase metal and polymer composite materials consisting of matrix and isotropic or anisotropic oriented deterministic fractal shapes made by 3D printing. By creating of reinforcing internal structure consisting of deterministic fractal connected shapes is possible to gain unlimited mechanical properties directing. These fractal shapes - placed in multiphase system matrix – are significantly influencing whole material system mechanical properties mainly in case of stress on the limit of strength, proportional elongation on the limit of strength or tensile/ flexural modulus. Fractal shapes are also possible to properly locate, orient or shape modify according to potential material using with goal to gain maximal efficiency of fractal shapes occurrence. Producing of this multiphase system is realized by the help of 3D printing technology. Internal fractal shape structure is 3D printed from aluminium. This feature is in the next step over injected by polymer. So is possible to create any fractal shapes placed in polymer matrix which are by another technology unmanufacturable. Mechanical properties analyse is performed with respect to fractal shape type, fractal dimension, and fractal shape orientation.
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Fatkullin, Ibrahim, and Valeriy Slastikov. "Limit Shapes for Gibbs Ensembles of Partitions." Journal of Statistical Physics 172, no. 6 (2018): 1545–63. http://dx.doi.org/10.1007/s10955-018-2117-7.
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Pittel, Boris, and Dan Romik. "Limit shapes for random square Young tableaux." Advances in Applied Mathematics 38, no. 2 (2007): 164–209. http://dx.doi.org/10.1016/j.aam.2005.12.005.
Full textDissertations / Theses on the topic "Limit shapes"
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Jonsson, Markus. "Processes on Integer Partitions and Their Limit Shapes." Doctoral thesis, Mälardalens högskola, Utbildningsvetenskap och Matematik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-35023.
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This thesis deals with processes on integer partitions and their limit shapes, with focus on deterministic and stochastic variants on one such process called Bulgarian solitaire. The main scientific contributions are the following. Paper I: Bulgarian solitaire is a dynamical system on integer partitions of n which converges to a unique fixed point if n=1+2+...+k is a triangular number. There are few results about the structure of the game tree, but when k tends to infinity the game tree itself converges to a structure that we are able to analyze. Its level sizes turns out to be a bisection of the Fibonacci numbers. The leaves in this tree structure are enumerated using Fibonacci numbers as well. We also demonstrate to which extent these results apply to the case when k is finite. Paper II: Bulgarian solitaire is played on n cards divided into several piles; a move consists of picking one card from each pile to form a new pile. In a recent generalization, σ-Bulgarian solitaire, the number of cards you pick from a pile is some function σ of the pile size, such that you pick σ(h) < h cards from a pile of size h. Here we consider a special class of such functions. Let us call σ well-behaved if σ(1) = 1 and if both σ(h) and h − σ(h) are non-decreasing functions of h. Well-behaved σ-Bulgarian solitaire has a geometric interpretation in terms of layers at certain levels being picked in each move. It also satisfies that if a stable configuration of n cards exists it is unique. Moreover, if piles are sorted in order of decreasing size then a configuration is convex if and only if it is a stable configuration of some well-behaved σ-Bulgarian solitaire. If sorted configurations are represented by Young diagrams and scaled down to have unit height and unit area, the stable configurations corresponding to an infinite sequence of well-behaved functions (σ1, σ2, ...) may tend to a limit shape Φ. We show that every convex Φ with certain properties can arise as the limit shape of some sequence of well-behaved σn. For the special case when σn(h) = ceil(qnh) for 0 < qn ≤ 1 (where ceil is the ceiling function rounding upward to the nearest integer), these limit shapes are triangular (in case qn2n → 0), or exponential (in case qn2n → ∞), or interpolating between these shapes (in case qn2n → C > 0). Paper III: We introduce pn-random qn-proportion Bulgarian solitaire (0 < pn,qn ≤ 1), played on n cards distributed in piles. In each pile, a number of cards equal to the proportion qn of the pile size rounded upward to the nearest integer are candidates to be picked. Each candidate card is picked with probability pn, independently of other candidate cards. This generalizes Popov's random Bulgarian solitaire, in which there is a single candidate card in each pile. Popov showed that a triangular limit shape is obtained for a fixed p as n tends to infinity. Here we let both pn and qn vary with n. We show that under the conditions qn2pnn/log n → ∞ and pnqn → 0 as n → ∞, the pn-random qn-proportion Bulgarian solitaire has an exponential limit shape. Paper IV: We consider two types of discrete-time Markov chains where the state space is a graded poset and the transitions are taken along the covering relations in the poset. The first type of Markov chain goes only in one direction, either up or down in the poset (an up chain or down chain). The second type toggles between two adjacent rank levels (an up-and-down chain). We introduce two compatibility concepts between the up-directed transition probabilities (an up rule) and the down-directed (a down rule), and we relate these to compatibility between up-and-down chains. This framework is used to prove a conjecture about a limit shape for a process on Young's lattice. Finally, we settle the questions whether the reverse of an up chain is a down chain for some down rule and whether there exists an up or down chain at all if the rank function is not bounded.
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Ahmed, Bako. "Limit Shapes for qVolume Tilings of a Large Hexagon." Thesis, KTH, Matematik (Avd.), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-280758.
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Lozenges are polygons constructed by gluing two equilateral triangles along an edge. We can fit lozenge pieces together to form larger polygons and given an appropriate polygon we can tile it with lozenges. Lozenge tilings of the semi-regular hexagon with sides A,B,C can be viewed as the 2D picture of a stack of cubes in a A x B x C box. In this project we investigate the typical shape of a tiling as the sides A,B,C of the box grow uniformly to infinity and we consider two cases: The uniform case where all tilings occur with equal probability and the q^Volume case where the probability of a tiling is proportional to the volume taken up by the corresponding stack of cubes. To investigate lozenge tilings we transform it into a question on families of non-intersecting paths on a corresponding graph representing the hexagon. Using the Lindström–Gessel–Viennot theorem we can define the probability of a non-intersecting path crossing a particular point in the hexagon both for the uniform and the $q$-Volume case. In each case this probability function is connected to either the Hahn or the $q$-Hahn orthogonal polynomials. The orthogonal polynomials depend on the sides of the hexagon and so we consider the asymptotic behaviour of the polynomials as the sides grow to infinity using a result due to Kuijlaars and Van Assche. This determines the density of non-intersecting paths through every point in the hexagon, which we calculate, and a ``Arctic curve" result which shows that the six corners of the hexagon are (with probability one) tiled with just one type of lozenge.<br>"Lozenger" är polygoner konstruerade genom att limma två liksidiga trianglar längs en kant. Vi kan montera lozengstycken ihop för att bilda större polygoner och med en lämplig polygon kan vi lozengplatta den. Lozengplattor av den semi-liksidiga hexagonen med sidorna A, B, C kan ses som 2D-bilden av en stapel kuber i en A x B x C-box. I det här projektet undersöker vi den typiska formen på en platta när sidorna A, B, C på rutan växer till oändlighet och vi tar an två fall: Det likformiga fallet där alla plattor sker med samma sannolikhet och q ^ Volymfallet då sannolikheten för en platta är proportionell mot volymen som tas upp av motsvarande kubstapel. För att undersöka plattor förvandlar vi det till en fråga om samlingar av icke-korsande vägar på en motsvarande graf som representerar hexagonen. Med hjälp av satsen Lindström – Gessel – Viennot kan vi definiera sannolikheten för att en icke-korsande väg går genom en viss punkt i hexagonen både för det enhetliga och $ q $ -volymfallet. I båda fallen är dessa sannolikhetsfunktioner relaterade till Hahn eller $ q $ -Hahn ortogonala polynomer. Dessa ortogonala polynom beror på hexagonens sidor så vi betraktar polynomens asymptotiska beteende när sidorna växer till oändlighet genom ett resultat från Kuijlaars och Van Assche. Detta bestämmer densiteten för de icke-korsande vägarna genom varje punkt i det hexagon vi beräknar. Detta bestämmer också också en '' arktisk kurva '' som visar att hexagonens sex hörn är (med sannolikhet ett) plattade med bara en typ av lozeng.
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Potka, Samu. "Limit shapes of standard Young tableaux and sorting networks via the Edelman-Greene correspondence." Licentiate thesis, KTH, Matematik (Avd.), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-235376.
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This thesis consists of the following two articles. New properties of the Edelman–Greene bijection. Edelman and Greene constructed a correspondence between reduced words of the reverse permutation and standard Young tableaux. We prove that for any reduced word the shape of the region of the insertion tableau containing the smallest possible entries evolves exactly as the upper-left component of the permutation’s (Rothe) diagram. Properties of the Edelman–Greene bijection restricted to 132-avoiding and 2143-avoiding permutations are presented. We also consider the Edelman-Greene bijection applied to non-reduced words. On random shifted standard Young tableaux and 132-avoiding sorting networks. We study shifted standard Young tableaux (SYT). The limiting surface of uniformly random shifted SYT of staircase shape is determined, with the integers in the SYT as heights. This implies via properties of the Edelman–Greene bijection results about random 132-avoiding sorting networks, including limit shapes for trajectories and intermediate permutations. Moreover, the expected number of adjacencies in SYT is considered. It is shown that on average each row and each column of a shifted SYT of staircase shape contains precisely one adjacency.<br><p>QC 20180926</p>
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Kuchumov, Nikolai. "Formes limites pour le modèle de dimères dans des domaines non simplement connexes." Electronic Thesis or Diss., Sorbonne université, 2024. http://www.theses.fr/2024SORUS281.
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Cette thèse se compose de trois parties, le but de la première partie est d'étudier les pavages aléatoires de dominos d'un domaine non simplement connexe avec une fonction de hauteur définie sur l'espace de revêtement universel du domaine. Nous établissons un principe de grandes déviations pour la fonction de hauteur dans deux régimes asymptotiques. Le premier régime couvre tous les pavages de dominos du domaine. Une loi des grands nombres pour le changement de hauteur dans ce régime est également obtenue. Le second régime couvre les pavages de dominos avec un changement de hauteur asymptotique donné. La deuxième partie de la thèse est une extension de la première partie. Nous prouvons l'existence d'une forme limite pour le modèle de dimères sur des graphes bipartis périodiques planaires avec un domaine fondamental arbitraire et des poids périodiques arbitraires. La troisième partie est consacrée au calcul de la courbe arctique du diamant aztèque avec trous dans deux régimes. Le premier régime, appelé cas non contraint, correspond à la mesure uniforme sur l'ensemble des pavages par dominos. Le second régime, appelé cas contraint, pose une condition sur le changement de hauteur des dominos<br>This thesis consists of three parts, the goal of the first part is to study random domino tilings of a multiply-connected domain with a height function defined on the universal covering space of the domain. We establish a large deviation principle for the height function in two asymptotic regimes. The first regime covers all domino tilings of the domain. A law of large numbers for height change in this regime will also be derived. The second regime covers domino tilings with a given asymptotic height change.The second part of thesis is an extension of the first part. We prove the existence of a limit shape for the dimer model on planar periodic bipartite graphs with an arbitrary fundamental domain and arbitrary periodic weights.The third part is devoted to computation of the arctic curve of the multiply-connected Aztec diamond in two regimes. The first regime, called an unconstrained case, corresponds to the uniform measure on a set of domino tilings. The second regime, constrained case, puts a condition on the height change of domino tilings
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Svoboda, Radek. "Návrh a posouzení ocelové konstrukce." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2017. http://www.nusl.cz/ntk/nusl-265683.
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Topic of the master’s thesis is design and assessment of steel construction of the industrial building used to glass sand treatment. The building has the top view dimensions 12,0 x 12,0 m and roof ridge height 15,6 m. Disposition if the individual elements was designed according to conditions of the technology and production process. The thesis focus on creating of computational model and assessment to ultimate and serviceability limit states of individual elements. Further thesis contains of design and optimisation of some joints.
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Podškubka, Patrik. "Zavěšená lávka pro pěší." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2016. http://www.nusl.cz/ntk/nusl-240250.
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The aim of this master’s thesis is a design of the footbridge that transfers separately pedestrian and bicycle traffic over the expressway and the local creek. Chosen footbridge, which were one of two possible designs, consists of a monolithic bridge deck suspended on the V-shaped pylon. Thesis contains a static calculation of the structure modeled in ANSYS software. Design and assessment are according to the current European standards
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Prasad, Rachit. "Time Spectral Adjoint Based Design for Flutter and Limit Cycle Oscillation Suppression." Diss., Virginia Tech, 2020. http://hdl.handle.net/10919/98574.
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When designing aircraft wings shapes, it is important to ensure that the flight envelope does not overlap with regions of flutter or Limit Cycle Oscillation (LCO). A quick assessment of these dynamic aeroelastic for various design candidates is key to successful design. Flutter based design requires the sensitivity of flutter parameters to be known with the respect of design parameters. Traditionally, frequency domain based methods have been used to predict flutter characteristics and its sensitivity. However, this approach is only applicable for linear or linearized models and cannot be applied to systems undergoing LCO or other nonlinear effects. Though the time accurate approach can be implemented to overcome this problem, it is computationally expensive. Also, the unsteady adjoint formulation for sensitivity analysis, requires the state and adjoint variables to be stored at every time step, which prohibitively increases the memory requirement. In this work, these problems have been overcome by implementing a time spectral method based approach to compute flutter onset, LCOs and their design sensitivities in a computationally efficient manner. The time spectral based formulation approximates the solution as a discrete Fourier series and directly solves for the periodic steady state, leading to a steady formulation. This can lead to the time spectral approach to be faster than the time accurate approach. More importantly, the steady formulation of the time spectral method also eliminates the memory issues faced by the unsteady adjoint formulation. The time spectral based flutter/LCO prediction method was used to predict flutter and LCO characteristics of the AGARD 445.6 wing and pitch/plunge airfoil section with NACA 64A010 airfoil. Furthermore, the adjoint based sensitivity analysis was used to carry out aerodynamic shape optimization, with an objective of maximizing the flutter velocity with and without constraints on the drag coefficient. The resulting designs show significant increase in the flutter velocity and the corresponding LCO velocity profile. The resulting airfoils display a greater sensitivity to the transonic shock which in turn leads to greater aerodynamic damping and hence leading to an increase in flutter velocity.<br>Doctor of Philosophy<br>When designing aircrafts, dynamic aeroelastic effects such as flutter onset and Limit Cycle Oscillations need to considered. At low enough flight speeds, any vibrations arising in the aircraft structure are damped out by the airflow. However, beyond a certain flight speed, instead of damping out the vibrations, the airflow accentuates these vibrations. This is known as flutter and it can lead to catastrophic structural failure. Hence, during the aircraft design phase, it must be ensured that the aircraft would not experience flutter during the flight conditions. One of the contribution of this work has been to come up with a fast and accurate method to predict flutter using computational modelling.
Depending on the scenario, it is also possible that during flutter, the vibrations in the structure increase to a certain amplitude before leveling off due to interaction of non-linear physics. This condition is known as limit cycle oscillation. While they can arise due to different kinds of non-linearities, in this work the focus has been on aerodynamic non-linearities arising from shocks in transonic flight conditions. While limit cycle oscillations are undesirable as they can cause structural fatigue, they can also save the aircraft from imminent structural fracture and hence it is important to accurately predict them as well. The main advantage of the method developed in this work is that the same method can be used to predict both the flutter onset condition and limit cycle oscillations. This is a novel development as most of the traditional approaches in dynamic aeroelasticity cannot predict both the effects.
The developed flutter/LCO prediction method has then been used in design with the goal of achieving superior flutter characteristics. In this study, the shape of the baseline airfoil is changed with the goal of increasing the flutter velocity. This enables the designed system to fly faster without addition of weight. Since the design has been carried out using gradient based optimization approach, an efficient way to compute the gradient needs to be used. Traditional approaches to compute the gradient, such as Finite Difference Method, have computational cost proportional to the number of design variables. This becomes a problem for shape design optimization, where a large number of design variables are required. This has been overcome by developing an adjoint based sensitivity analysis method. The main advantage of the adjoint based sensitivity analysis is that it its computational cost is independent of the number of design variables, and hence a large number of design variables can be accommodated. The developed flutter/LCO prediction and adjoint based sensitivity analysis framework was used to carry out shape design for a pitch/plunge airfoil section. The objective of the design process was to maximize the flutter onset velocity with and without constraints on drag. The resulting optimized airfoils showed significant increase in the flutter velocity.
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Lawrence, Adam. "Investigating the limits of how expectation can shape affective judgement." Thesis, University of Manchester, 2017. https://www.research.manchester.ac.uk/portal/en/theses/investigating-the-limits-of-how-expectation-can-shape-affective-judgement(1a10bbf9-1db7-481f-b350-dba27a65e282).html.
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The generation of predictions shapes our experience of the world around us. By making inferences about what is likely to happen within a given scenario, we can conserve cognitive resources and enhance our prospects of survival. Predictive coding accounts of perception indicate that this is achieved by minimally processing information that is consistent with our expectations, and prioritising the processing of unexpected or meaningful information. Predictions are also beneficial in situations where accurate perception is difficult, and clues like contextual information allow expectations to ‘fill in the blanks’ when sensory information is noisy or ambiguous. This comes at a cost, however, and a reliance upon expectations can lead to perceptual biases, and in certain cases misperceptions. According to Assimilation Contrast Theory (ACT) and the Affective Expectation Model (AEM), when we attempt to judge affectively ambiguous stimuli, our judgements are biased by expectations in a similar manner. If stimuli are within an acceptable range of an existing expectation, minor discrepancies will be ignored and judgements of those stimuli will fall in line with expectations (assimilation). Alternatively, if the affective discrepancy between expectation and stimulus is so large that it is acknowledged, the extent of that discrepancy will be exaggerated instead (contrast). This thesis aimed to investigate the boundaries and time-course of these effects. A series of behavioural experiments were conducted to investigate: (i) whether predictive cues promoted a state of affective readiness, where judgements across a range of stimuli were biased based upon the assumption that they were broadly part of a positive or negative category (chapters 3 and 4); (ii) whether affective biases (assimilation effects) persisted over time (chapters 5 and 6); and (iii) whether the boundaries of affective and perceptual assimilation effects remained consistent over time (chapter 6 and 7). Psychophysical measures of affective bias indicated that predictive cues influenced participants to judge the same stimuli differently, according to whether they expected those stimuli to be positive or negative. Furthermore, after expectations were learned, judgements of the same stimuli continued to be biased toward expectations after a period of one week. When stimuli from affectively or perceptually distinct categories were manipulated slowly over time, to the point where they became identical, judgements of those stimuli continued to be influenced by the expectation that they should remain distinct. These findings indicate that the boundaries of perceptual and affective assimilation effects may not be static, and if deviations from expectation are small enough to go generally unnoticed, people may update their internal representations of items over time, and the boundaries of acceptance which surround those representations.
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Diermeier, Johannes [Verfasser]. "Analysis of martensitic microstructures in shape-memory-alloys: A low volume-fraction limit / Johannes Diermeier." Bonn : Universitäts- und Landesbibliothek Bonn, 2016. http://d-nb.info/1122193939/34.
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Martins, Leandro Filipe Correia. "Santuário de Nossa Senhora do Cabo Espichel." Master's thesis, Universidade de Lisboa, Faculdade de Arquitetura, 2017. http://hdl.handle.net/10400.5/13854.
Full textBooks on the topic "Limit shapes"
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Hora, Akihito. The Limit Shape Problem for Ensembles of Young Diagrams. Springer Japan, 2016. http://dx.doi.org/10.1007/978-4-431-56487-4.
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Golub, Edward S. The limits of medicine: How science shapes our hope for the cure. University of Chicago Press, 1997.
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Mason, Nick. At the limit: Twenty-one classic cars that shaped a century of motor sport. MBI Pub. Co., 1998.
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Billé, Franck, Sanjyot Mehendale, and James W. Lankton. The Maritime Silk Road. Amsterdam University Press, 2022. http://dx.doi.org/10.5117/9789463722247.
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The Maritime Silk Road foregrounds the numerous networks that have been woven across oceanic geographies, tying world regions together often far more extensively than land-based routes. On the strength of the new data which has emerged in the last two decades in the form of archaeological findings, as well as new techniques such as GIS modeling, the authors collectively demonstrate the existence of a very early global maritime trade. From architecture to cuisine, and language to clothing, evidence points to early connections both within Asia and between Asia and other continents—well before European explorations of the Global South. The human stories presented here offer insights into both the extent and limits of this global exchange, showing how goods and people traveled vast distances, how they were embedded in regional networks, and how local cultures were shaped as a result.
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Lagerkvist, Amanda. Existential Media. Oxford University Press, 2022. http://dx.doi.org/10.1093/oso/9780190925567.001.0001.
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This book offers a reappreciation and revisiting of existential philosophy—and in particular of Karl Jaspers’s philosophy—for media theory in order to remedy the existential deficit in the field. The book thereby also offers an introduction to the young field of existential media studies. Jaspers’s concept of the limit situation is chosen as a privileged reality which allows for bringing limits, in all their shapes and forms, onto the radar when interrogating digital existence. Despite their all-pervasiveness the book argues that media speak to and about limits and limitations in a variety of ways. The book furthermore argues that the present age of deep technocultural saturation—and of escalating multifaceted and interrelated global crises—is a digital limit situation, in which there are both existential and politico-ethical stakes of media. To enter into these terrains, the book places the margin of mourners and the meek—the coexisters—at the center of media studies. The book provides an alternative mapping for approaching digital cultures in contexts of both the mundane and the extraordinary, and on scales traversing the individual and the global. Empirically Existental Media attends to mourning, commemorating, and speaking to the dead online as well as to the digital afterlife. It interrogates four cases that center on the voices from the field of online bereavement, and provides an arc of media instantiations of the digital limit situation: chapter 5: Metric Media; chapter 6: Caring Media, chapter 7: Transcendent Media and chapter 8: Anticipatory media.
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Hora, Akihito. Limit Shape Problem for Ensembles of Young Diagrams. Springer, 2016.
Find full textBook chapters on the topic "Limit shapes"
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Goncharova, Elena, and Alexander Ovseevich. "Limit Shapes of Reachable Sets for Linear Control Systems." In Large-Scale Scientific Computing. Springer Berlin Heidelberg, 2006. http://dx.doi.org/10.1007/11666806_25.
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Piché, Luc, and André Hamel. "Characterization of Isotropic Composites Containing Inclusions of Specified Shapes by use of Ultrasonics In The Long Wavelength Limit." In Nondestructive Characterization of Materials II. Springer US, 1987. http://dx.doi.org/10.1007/978-1-4684-5338-6_10.
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Fiddes, Paul S. "The Shape of the Story." In Freedom and Limit. Palgrave Macmillan UK, 1991. http://dx.doi.org/10.1057/9780230389823_3.
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van Grunsven, Janna, Bouke van Balen, and Caroline Bollen. "10. Three Embodied Dimensions of Communication." In Phenomenology and the Philosophy of Technology. Open Book Publishers, 2024. http://dx.doi.org/10.11647/obp.0421.10.
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In the last chapter, Janna van Grunsven, Caroline Bollen and Bouke van Balen show how the phenomenology of communication can inform the field of augmented or alternative communication technology (AAC-tech). AAC-tech is a set of technologies developed for people who are unable to use some of their bodily expressive resources due to congenital or acquired disability. This inability often makes it very difficult for those people to communicate. Developers of AAC-tech often take a cognitivist starting-point, thereby missing out on the subtle ways in which embodiment shapes communication. The phenomenological description of the lived experiences of these people offers a fruitful starting-point for recognizing the often forgotten embodied dimension of communication, and enables to formulate desiderata for how AAC-tech should be developed: AAC-tech should take into account (1) embodied address, (2) embodied enrichment, and (3) embodied diversity. Focusing on the lived experience of potential users of AAC-tech has, according to van Grunsven, Bollen, and van Balen, not only direct practical applications for technology development but also can inform phenomenology methodologically: focusing on a limit case as the one discussed in this chapter makes visible that communication takes place in a wide variety of ways and that it is not the task of the phenomenologist to lay bare a general or essential structure of communication that can be taken as a standard.
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Flucher, Martin. "Concentration and Limit Shape of Low Energy Extremals." In Variational Problems with Concentration. Birkhäuser Basel, 1999. http://dx.doi.org/10.1007/978-3-0348-8687-1_7.
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Daniel, Jérémie, and Jean-Philippe Lauffenburger. "Multi-level Dempster-Shafer Speed Limit Assistant." In Advances in Intelligent and Soft Computing. Springer Berlin Heidelberg, 2012. http://dx.doi.org/10.1007/978-3-642-29461-7_38.
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Chao, Yi, and Dong Jun. "Research on the Influence of Transverse Limit of Support on Construction Monitoring of Special-Shaped Bridge." In Lecture Notes in Civil Engineering. Springer Singapore, 2022. http://dx.doi.org/10.1007/978-981-19-1260-3_13.
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AbstractIn order to understand whether the alignment, internal force and cable force of the special-shaped cable-stayed bridge can still meet the design and code requirements due to the influence of the transverse displacement of the support during the construction process, the transverse displacement of the girder arch system is restricted before the removal of the support. The difference between the measured value and the designed value at each stage of the boom is within ±5%, which meets the design and specification requirements. In this paper, the pedestrian bridge in Anyi County, Nanchang City, Jiangxi Province is taken as an example. MADIS/Civil software is used for finite element simulation analysis in the construction stage, and the linear shape, internal force and cable force of the superstructure are monitored. The results show that the measured deformation values of arch ribs and beams meet the design and specification requirements during the whole construction process. The difference between the measured value and the designed value at each stage of the boom is within ±5%, which meets the design and specification requirements.
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Georgiou, D. P., and N. G. Theodoropoulos. "The Loading of Water Current Turbines: The Betz Limit and Ducted Turbines." In Alternative Energy and Shale Gas Encyclopedia. John Wiley & Sons, Inc., 2016. http://dx.doi.org/10.1002/9781119066354.ch58.
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Chen, Ye, and Bo Qin Gu. "Design Technology of Ω-Shaped Seal Ring Based on Plastic Limit Analysis." In Key Engineering Materials. Trans Tech Publications Ltd., 2007. http://dx.doi.org/10.4028/0-87849-456-1.2691.
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McGillen, Michael. "The Eschatological Limit." In Shapes of Time. Cornell University Press, 2023. http://dx.doi.org/10.7591/cornell/9781501772818.003.0003.
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This chapter focuses on the notion of eschatological limits in correlation with spatial form in Karl Barth's Dialectical Theology. A centerpiece of Barth's theory of the moment can be found in the notion of “time of the now,” a concept whose eschatological energies imply both a radical negation of historical time and its paradoxical redemption. In his articulation of paradoxes, Barth's work bears the stamp of modernity wherein he conceptualizes the temporal dislocation of the moment by drawing on the resources of spatial form. The chapter elaborates on Dialectical Theology's perception of time as its limit. Barth's The Epistle to the Romans serves as a paradigmatic example of how modernism's spatial forms provided alternatives to the construction of history in historicism.
Conference papers on the topic "Limit shapes"
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KENYON, RICHARD. "LIMIT SHAPES AND THEIR ANALYTIC PARAMETERIZATIONS." In International Congress of Mathematicians 2018. WORLD SCIENTIFIC, 2019. http://dx.doi.org/10.1142/9789813272880_0175.
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Vance, Robert, and Indrek S. Wichman. "Heat Loss Analysis of Flamelets in Near-Limit Spread Over Solid Fuel Surfaces." In ASME 2001 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2001. http://dx.doi.org/10.1115/imece2001/htd-24252.
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Abstract The profile of a spreading flamelet is analyzed by examining the heat losses to surrounding surfaces. The study addresses the reasons why flamelets have shapes ranging from round hemispherical “caps” to flat “coin-like” discs. A parabolic shape profile is used for the thin flame sheet, which provides both flame length and flame curvature. A third parameter specifies the height of the flame from the surface beneath it. Radiation and conduction heat losses from the flame sheet are calculated for various flame shapes. Overall heat losses as well as heat losses to the surface beneath the flamelet are examined. Some of the heat “losses” are misnamed because they produce the necessary surface decomposition for subsequent gaseous flame fuel vapors. Strictly, then, “losses” do not contribute appreciably to the maintenance of the flame. Physical arguments are made to explain observed flame spread behavior and flame shapes in response to prevailing flow and environmental conditions.
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Boulet, C., and J. Boissoles. "Line mixing effects in the impact limit: ECS analysis of various experiments made on some IR bands of CO2 in helium." In Proceedings of the 12th International conference on spectral line shapes. AIP, 1995. http://dx.doi.org/10.1063/1.47511.
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Park, Chi-Yong, Sung-Ho Lee, Yun-Jae Kim, Chang-Kyun Oh, and No-Hoon Myeng. "Axial Length and Shape Effects of Local Wall Thinning on Net-Section Limit Loads." In ASME 2007 Pressure Vessels and Piping Conference. ASMEDC, 2007. http://dx.doi.org/10.1115/pvp2007-26225.
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This paper provides plastic limit loads of pipes with local wall thinning under internal pressure and under bending, by quantifying effects of the axial extent and the shape of local wall thinning. The effect of the axial extent on plastic limit loads is not so significant for bending but could be more significant for internal pressure. It is also found that the effect of the shape of local wall thinning on limit loads could be quite significant. Thus idealization of local wall thinning as rectangular shapes rather than circular ones could lead to significantly conservative estimates of maximum loads, which is also supported by comparison with published full-scale pipe test data.
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Dang, T. Q., A. C. Nerurkar, and D. R. Reddy. "Design Modification of Rotor 67 by 3D Inverse Method — Inviscid-Flow Limit." In ASME 1997 International Gas Turbine and Aeroengine Congress and Exhibition. American Society of Mechanical Engineers, 1997. http://dx.doi.org/10.1115/97-gt-484.
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A design modification of Rotor 67 is carried out with a full 3D inverse method. The blade camber surface is modified to produce a prescribed pressure loading distribution, with the blade tangential thickness distribution and the blade stacking line at midchord kept the same as the original Rotor 67 design. Because of the inviscid-flow assumption used in the current version of the method, Rotor 67 geometry is modified for use at a design point different from the original design value. In the subsonic section, smooth pressure loading shapes generally produce blades with well-behaved blade surface pressure distributions. In the supersonic section, this study shows that the strength and position of the passage shock correlate with the characteristics of the blade pressure loading shape. In general, “smooth” prescribed blade pressure loading distributions generate blade designs with reverse cambers which have the effect of weakening the passage shock.
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Ali, Rehab Kotb, Ahmed Hamed Fatehy, and James Word. "Exploring patterning limit and enhancement techniques to improve printability of 2D shapes at 3nm node." In Design-Process-Technology Co-optimization for Manufacturability XIV, edited by Chi-Min Yuan and Ryoung-Han Kim. SPIE, 2020. http://dx.doi.org/10.1117/12.2552091.
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Mehrizi, Amir, Soheil Nakhodchi, and Reza Adibi-Asl. "Limit Load Analysis of a Torispherical Head With Thermal Hot Spot Damage." In ASME 2018 Pressure Vessels and Piping Conference. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/pvp2018-84990.
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Vessel dished heads are widely being used in storage tanks or pressure vessels. These heads are available in different shapes including hemispherical, ellipsoidal and torispherical heads. In this paper, pressure limit load of torispherical head with thermal hotspot damage is investigated. Thermal hotspots are one of the common types of in-service degradation in some pressurized components and can be considered as damage. This type of damage is usually caused by the loss of refractory lining on the inside wall of pressure components or due to a misdistribution of the flow within vessels containing catalysts. Hotspot damage potentially jeopardizes the integrity of the components [1]. In the current research, the impact of a thermal hotspot on the load carrying capacity of various shapes of torispherical heads is investigated using numerical simulation. Also, sensitivity analysis has been performed to investigate the effect of location of thermal hot spots and thickness in the torispherical heads, with and without thermal hot spot damage.
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Jie, M., C. Chow, C. H. Cheng, and L. C. Chan. "Forming Limit Analysis of Aluminum Tailor-Welded Blanks." In ASME 2005 International Mechanical Engineering Congress and Exposition. ASMEDC, 2005. http://dx.doi.org/10.1115/imece2005-79915.
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This paper presents an investigation on forming limits of tailor-welded blanks (TWBs) made of 5754-O aluminum sheets using both experimental and numerical approaches. A TWB is composed of two or more welded flat metal sheet of different thicknesses, shapes or mechanical properties. Due to the existence of weldment and the individual configurations of parent blanks, a TWB should be considered as heterogeneous in its structure. The mechanical properties of those parent metals and weld metal required for the simulation were measured individually. With the aid of the acquired data, finite element simulations for analyzing the forming process of TWBs were carried out using a general purpose finite element package, LS-DYNA. A localized necking criterion based on the vertex theory is employed to predict forming limit strains and failure locations of the aluminum TWBs. The theoretical predictions were satisfactorily validated with those obtained from the experiments.
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Rana, Mahendra D., Victor E. Bergsten, and Yogeshwar Hari. "Limit Load Analysis of API 620 Tank Roof-Shell Junction." In ASME 2002 Pressure Vessels and Piping Conference. ASMEDC, 2002. http://dx.doi.org/10.1115/pvp2002-1243.
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The compression ring at a tank’s roof-shell junction has been designed using the API 620 [1] rules. The geometrical configuration of the ring is non-conventional compared to the typical shapes recommended in API 620. In order to verify the structural integrity of the roof-shell junction, a plastic FEA was conducted to establish the maximum allowable working pressure (MAWP) using a limit load analysis procedure. The FEA results indicated that the tank’s roof-shell junction’s MAWP is 18.7 psi which exceeds the calculated MAWP of 15 psi using the API 620 rules. This paper presents the comparisons of the MAWPs calculated using the API 620 rules and the plastic FEA.
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Kim, TaeRyong, and ChangKyun Oh. "Limit Load Analysis of Pipe Bend With Extrados Wall Thinning." In 2014 22nd International Conference on Nuclear Engineering. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/icone22-31000.
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Since pipe bend has a characteristic that extrados becomes thinner and intrados thicker after fabrication process, it can be expected to be vulnerable to extrados wall thinning due to corrosion or erosion during its operation. In this paper, limit loads of pipe bend with the thinning are computed under the loading conditions of internal pressure and bending moment. Several case studies with varying geometries and wall thinning shapes are presented. The difference in the limit loads behavior between pipe bend and welded elbow is also reviewed. The calculated plastic limit loads of pipe bend are compared with other research results for the welded elbow. The results show that pipe bend can be applied to safety-related piping systems as far as the internal pressure and bending moment only are considered.
Reports on the topic "Limit shapes"
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Pawlowski, Wojtek P., and Avraham A. Levy. What shapes the crossover landscape in maize and wheat and how can we modify it. United States Department of Agriculture, 2015. http://dx.doi.org/10.32747/2015.7600025.bard.
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Meiotic recombination is a process in which homologous chromosomes engage in the exchange of DNA segments, creating gametes with new genetic makeup and progeny with new traits. The genetic diversity generated in this way is the main engine of crop improvement in sexually reproducing plants. Understanding regulation of this process, particularly the regulation of the rate and location of recombination events, and devising ways of modifying them, was the major motivation of this project. The project was carried out in maize and wheat, two leading crops, in which any advance in the breeder’s toolbox can have a huge impact on food production. Preliminary work done in the USA and Israeli labs had established a strong basis to address these questions. The USA lab pioneered the ability to map sites where recombination is initiated via the induction of double-strand breaks in chromosomal DNA. It has a long experience in cytological analysis of meiosis. The Israeli lab has expertise in high resolution mapping of crossover sites and has done pioneering work on the importance of epigenetic modifications for crossover distribution. It has identified genes that limit the rates of recombination. Our working hypothesis was that an integrative analysis of double-strand breaks, crossovers, and epigenetic data will increase our understanding of how meiotic recombination is regulated and will enhance our ability to manipulate it. The specific objectives of the project were: To analyze the connection between double-strand breaks, crossover, and epigenetic marks in maize and wheat. Protocols developed for double-strand breaks mapping in maize were applied to wheat. A detailed analysis of existing and new data in maize was conducted to map crossovers at high resolution and search for DNA sequence motifs underlying crossover hotspots. Epigenetic modifications along maize chromosomes were analyzed as well. Finally, a computational analysis tested various hypotheses on the importance of chromatin structure and specific epigenetic modifications in determining the locations of double-strand breaks and crossovers along chromosomes. Transient knockdowns of meiotic genes that suppress homologous recombination were carried out in wheat using Virus-Induced Gene Silencing. The target genes were orthologs of FANCM, DDM1, MET1, RECQ4, and XRCC2.
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Holz, Ceecee. Are G20 countries doing their fair share of global climate mitigation?: Comparing ambition and fair shares assessments of G20 countries' nationally determined contributions (NDCs). Oxfam International, 2023. http://dx.doi.org/10.21201/2023.621540.
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As the group of the world’s largest economies and biggest emitters, G20 countries are central to implementing solutions to the climate emergency. This discussion paper assesses to what extent they are setting climate mitigation targets that are ambitious enough and/or meet their fair share of global emissions reductions consistent with limiting global heating to 1.5°C. It applies three different methodologies to assess their pledges. Despite some differences between these methodologies, the paper finds that the G20 countries – both collectively, and almost all of them individually – are failing to achieve their fair share of ambitious global mitigation required to limit global heating to 1.5°C, regardless of which assessment methodology is applied. Additionally, the assessment shows that the high-income G20 member countries are pledging to do a much smaller fraction of their fair share as compared to the middle-income countries. The G7 countries among the G20, in particular, appear to now be focusing their attention on the increase of ambition of middle-income and low-income countries while not recognising the need to also substantially increase the ambition in their own 2030 pledges. Additionally, the G7 countries continue to fail to recognise the need to commit to individual long-term climate finance to low and middle-income countries, at a scale much higher than what they currently provide, to enable rapid and just transitions to climate-resilient and low-carbon societies powered by renewable energy. This analysis highlights that G20 countries must both urgently, and before COP28 in December 2023, raise the ambition of their pledges for action by 2030, ramp up their provision of international climate finance and increase their international cooperation and support.
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Yoosef-Ghodsi, Ozkan, and Bandstra. PR-244-114501-R01 Review of Compressive Strain Capacity Assessment Methods Final Report. Pipeline Research Council International, Inc. (PRCI), 2013. http://dx.doi.org/10.55274/r0010402.
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Buried pipelines subjected to non-continuous ground movement such as frost heave, thaw settlement, slope instability and seismic movement experience high compressive strains that can cause local buckling (or wrinkling), in which the pipe wall buckles like a thin cylindrical shell in axial compression. In a strain-based design and assessment framework, excessive local buckling deformation that may cause loss of serviceability, or even pressure containment in some cases, is managed by limiting the strain demand below the strain limit. The determination of compressive strain limit is typically performed by full-scale structural testing or nonlinear finite element analysis that takes into account material and geometric non-linearity associated with the inelastic buckling of cylindrical shells. Before performing testing and numerical analysis (or when such options do not exist), empirical equations are used to estimate the strain limit. In this report a number of representative equations were evaluated by comparing strain limit predictions to full-scale test results. Work prior to this study has identified the importance of key variables that have the greatest impact on the local buckling behaviour. Examples of these variables include the diameter-to-thickness (D/t) ratio, internal pressure and shape of the stress strain curve. The evaluation focused on how existing equations address these key variables, and the performance with respect to key variables and in different ranges.
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Fernandez, Ruben, Hernando Lugo, and Georfe Dulikravich. Aerodynamic Shape Multi-Objective Optimization for SAE Aero Design Competition Aircraft. Florida International University, 2021. http://dx.doi.org/10.25148/mmeurs.009778.
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The SAE Regular Class Aero Design Competition requires students to design a radio-controlled aircraft with limits to the aircraft power consumption, take-off distance, and wingspan, while maximizing the amount of payload it can carry. As a result, the aircraft should be designed subject to these simultaneous and contradicting objectives: 1) minimize the aerodynamic drag force, 2) minimize the aerodynamic pitching moment, and 3) maximize the aerodynamic lift force. In this study, we optimized the geometric design variables of a biplane configuration using 3D aerodynamic analysis using the ANSYS Fluent. Coefficients of lift, drag, and pitching moment were determined from the completed 3D CFD simulations. Extracted coefficients were used in modeFRONTIER multi-objective optimization software to find a set of non-dominated (Pareto-optimal or best trade-off) optimized 3D aircraft shapes from which the winner was selected based to the desired plane performance.
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Baker, James E. Ethics and Artificial Intelligence: A Policymaker's Introduction. Center for Security and Emerging Technology, 2021. http://dx.doi.org/10.51593/20190022.
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The law plays a vital role in how artificial intelligence can be developed and used in ethical ways. But the law is not enough when it contains gaps due to lack of a federal nexus, interest, or the political will to legislate. And law may be too much if it imposes regulatory rigidity and burdens when flexibility and innovation are required. Sound ethical codes and principles concerning AI can help fill legal gaps. In this paper, CSET Distinguished Fellow James E. Baker offers a primer on the limits and promise of three mechanisms to help shape a regulatory regime that maximizes the benefits of AI and minimizes its potential harms.
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Roth, Christian. Design of the In-vehicle Experience. SAE International, 2022. http://dx.doi.org/10.4271/epr2022012.
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The in-vehicle experience, both physical and digital, is increasingly the differentiating factor between vehicles. Since touch displays, smart surfaces, and internet connectivity are present in most vehicle segments, the growing resemblance of in-vehicle experiences with mobile experiences leads to user expectations on par with smartphones. While manufacturers are faced with providing suitable service offerings that are safe to use, they must also identify services to exclude or limit, without encouraging drivers to resort back to their mobile devices. This increasingly complex in-vehicle experience design process is being shaped by new stakeholders, including operating system providers and application developers. Design of the In-vehicle Experience examines the challenging and changing relationships between manufacturers (that lack in software development and mobile experience design skills) and new stakeholders (that lack the decades of experience designing for the driving context). The report also discusses augmenting and expanding existing guidelines and best practices to address the challenges of modern in-vehicle experience design.
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Brosnahan and DeVries. PR-317-10702-R01 Testing for the Dilation Strength of Salt. Pipeline Research Council International, Inc. (PRCI), 2011. http://dx.doi.org/10.55274/r0010026.
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A laboratory testing program on rock salt specimens was performed using test conditions that are consistent with the stresses that are experienced near the surfaces of salt caverns during storage operation. The proposed work effort focuses on improving the methodology for defining the onset of dilation for rock salt. Geomechanical studies use dilation criteria to assess the potential for salt damage that can lead to spalling in the cavern roof and/or walls and subsequent damage to the cavern or hanging string. This constraint is often the one that limits the minimum gas pressure in a natural gas storage cavern. This report documents the PRCI funded follow-on activities to the recently completed Gas Storage Technology Consortium project [DeVries, 2010]. The work activities completed include the following: Laboratory dilation strength testing of eight specimens having preconditioning durations longer than 10 days. Numerical modeling to identify and optimize an appropriate specimen shape for dilation testing in triaxial extension states of stress. Laboratory constant mean stress extension testing on the optimized specimen shape. DeVries [2010] documented the effects of the preconditioning durations on the dilation strength of salt specimens. Preconditioning of specimens is the process whereby specimens are subject to a relatively high hydrostatic stress for a specified period of time. It is believed that preconditioning mitigates some of the damage to the specimens induced by coring, transporting, and specimen preparation. The study documented by DeVries [2010] suggests that increasing the preconditioning duration increases the dilation strength of salt, with the maximum precondition duration limited to 10 days. This project expands upon these findings through additional testing to determine if preconditioning durations longer than 10 days has any additional benefit. In addition to the preconditioning task, this study will also investigate the variability issues observed during dilation strength tests performed under triaxial extension states of stress. It is hypothesized that the high variability seen in extensional test results might be attributed to end effects caused by (1) the friction at the specimen-platen interface and (2) specimens breaking outside the range measured by gages. To help reduce frictional effects and breakage location issues, numerical models of alternate specimen shapes were created to provide a basis for testing a new specimen geometry. Laboratory tests were performed on the new specimen geometry to validate any of its possible benefits.
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Martin, Dougal, Juan José Durante, and Ben Rowland. Belize: A Private Sector Assessment: Private Sector Development Discussion Paper #6. Inter-American Development Bank, 2010. http://dx.doi.org/10.18235/0006918.
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Two basic factors shape private sector development in Belize. First, the population is small - only 322,000 as of mid-2008. This limits the size of the domestic market and potential economies of scale. The economy was only US$1.3 billion in 2009 and diversification is limited. The economy depends strongly on trade with the world economy, both as a market for domestic produce and as a source of the wide range of products that would be costly or impossible to produce domestically. Aside from Caribbean micro-states, Belize is the fourth most open economy in Latin America and the Caribbean (Figure 1). Any strategy to promote private sector development has to recognize that growth will continue to be export-led. The purpose of this study has been to describe Belize's private sector which accounts for roughly two-thirds of the economy.
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Banga, Karishma, and Alexander Beyleveld. Are Trade Rules Undermining Taxation of the Digital Economy in Africa? Institute of Development Studies, 2024. http://dx.doi.org/10.19088/ictd.2024.007.
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African countries are currently considering provisions in the AfCFTA and at the WTO to liberalise digital trade. As they face mounting fiscal pressures, it is imperative that they beware the implications of digital trade provisions for their ability to tax their digital economy. In this paper, we develop a comprehensive framework for analysing the impact of trade rules on tax regimes in the digital economy, with a focus on Kenya, Rwanda, and South Africa. We explore how trade rules ostensibly shape tax policies and their implications for revenue generation. By examining rules regulating trade in services and the imposition of customs duties on electronic transmissions, we identify how these rules may directly impact tax policies and limit revenue generation possibilities. Moreover, digital trade rules, such as those related to data flows, localisation, and source code sharing, have the capacity to produce both indirect and administrative effects on tax measures. These rules can alter tax structures, taxation rights, data collection, and the capacity to monitor and implement tax measures. Our findings shed light on the complex interplay between trade rules and tax measures, highlighting potential challenges and opportunities for revenue generation from the digital economy in African countries.
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Rokhideh, Maryam. Leveraging the Peacebuilding Potential of Cross-border Trader Networks in Sub-Saharan Africa. RESOLVE Network, 2021. http://dx.doi.org/10.37805/pn2021.17.lpbi.
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Cross-border trade plays a prominent role in economic, social, and political life in Sub-Saharan Africa, contributing significantly to development, poverty reduction, and job creation. Across the continent, cross-border trade accounts for 43 percent of the entire population’s income. As actors embedded in licit and illicit networks at local and regional levels, cross-border traders have the potential to fuel conflict or mitigate it. They can act as spoilers, supporting armed groups and war economies, or as peace intermediaries, negotiating peace deals and bridging conflict divides across communities. Given that most armed conflicts in Sub-Saharan Africa are shaped by cross-border dynamics, cross-border traders present an underexamined yet critical point of entry for analyzing and addressing conflicts and should be included in new and ongoing peacebuilding programming. This policy note provides recommendations on how policymakers can leverage the untapped peacebuilding potential of cross-border traders and decrease their spoiling power.