Academic literature on the topic 'Area Projection Transform'
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Journal articles on the topic "Area Projection Transform"
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YANG, JIANWEI, LIANG ZHANG, and ZHENGDA LU. "THE MELLIN CENTRAL PROJECTION TRANSFORM." ANZIAM Journal 58, no. 3-4 (March 7, 2017): 256–64. http://dx.doi.org/10.1017/s1446181116000341.
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The central projection transform can be employed to extract invariant features by combining contour-based and region-based methods. However, the central projection transform only considers the accumulation of the pixels along the radial direction. Consequently, information along the radial direction is inevitably lost. In this paper, we propose the Mellin central projection transform to extract affine invariant features. The radial factor introduced by the Mellin transform, makes up for the loss of information along the radial direction by the central projection transform. The Mellin central projection transform can convert any object into a closed curve as a central projection transform, so the central projection transform is only a special case of the Mellin central projection transform. We prove that closed curves extracted from the original image and the affine transformed image by the Mellin central projection transform satisfy the same affine transform relationship. A method is provided for the extraction of affine invariants by employing the area of closed curves derived by the Mellin central projection transform. Experiments have been conducted on some printed Chinese characters and the results establish the invariance and robustness of the extracted features.
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Dorrek, Felix, and Franz E. Schuster. "Projection functions, area measures and the Alesker–Fourier transform." Journal of Functional Analysis 273, no. 6 (September 2017): 2026–69. http://dx.doi.org/10.1016/j.jfa.2017.06.003.
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Zhou, Xiaohui, and Baoqin Wang. "Wavelet analysis on some smooth surface with nonzero constant Gaussian curvature." International Journal of Wavelets, Multiresolution and Information Processing 16, no. 01 (January 2018): 1850007. http://dx.doi.org/10.1142/s0219691318500078.
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According to the theory of wavelet analysis on [Formula: see text], the wavelet analysis on a smooth surface [Formula: see text] with nonzero constant Gaussian curvature will be discussed systematically in this paper. First, a general area-preserving projection from a smooth surface to the plane will be presented by the Gaussian projection and the area-preserving projection on the sphere. Then the continuous wavelet transform and its inverse transform on a smooth surface [Formula: see text] with nonzero constant Gaussian curvature will be discussed by a general area-preserving projection, relative dilation operator and translation operator. Further, according to the multi-resolution analysis on a smooth surface, the discrete wavelet transform and relative properties will be investigated systematically, including the two-scale equations of the wavelet function, orthogonality and so on. Finally, two numerical examples will be given.
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Wang, Bao Qin, Gang Wang, Xiao Hui Zhou, and Yu Su. "Wavelet analysis on developable surface base on area preserving projection." International Journal of Wavelets, Multiresolution and Information Processing 13, no. 01 (January 2015): 1550007. http://dx.doi.org/10.1142/s0219691315500071.
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In this paper, a simple method is given in order to construct an area preserving mapping from a developable surface M to a plane. Based on the area preserving projection, we give some important formulas on M, and define a multi-resolution analysis on L2(M). We provide the conditions to further discuss the continuous wavelet transform and discrete wavelet transform on developable surface. At the same time, we derived two-scale equations that the scaling function and wavelet function on developable surface satisfied, we also define and discuss the orthogonality, and several important theorems are given. Finally, we construct the numerical examples. The focus of this paper is the area preserving mapping that from developable surface M to a plane, and the discrete wavelet transform on developable surface.
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MA, Tong Yi, and Li Li Zhang. "Lp−Winterniz problem on firey projection of convex bodies." Tamkang Journal of Mathematics 45, no. 2 (June 30, 2014): 179–93. http://dx.doi.org/10.5556/j.tkjm.45.2014.1017.
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For $p\geq 1$, Lutwak, Yang and Zhang introduced the concept of $p$-projection body, and Lutwak introduced the concept of $L_{p}-$ affine surface area of convex body. In this paper, we develop the Minkowski-Funk transform approach in the $L_{p}$-Brunn-Minkowski theory. We consider the question of whether $\Pi_{p}K\subseteq \Pi_{p}L$ implies $\Omega_{p}(K) \leq \Omega_{p}(L)$, where $\Pi_{p}K$ and $\Omega_{p}K$ denotes the $p-$projection body of convex body $K$ and the $L_{p}-$affine surface area of convex body $K$, respectively. We also formulate and solve a generalized $L_{p}-$Winterniz problem for Firey projections.
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Suzuki, Sodai, Yuichi Akatsuka, Wei Jiang, Motoharu Fujigaki, and Masaaki Otsu. "Development of Quick Three-Dimensional Shape Measurement Projection Mapping System Using a Whole-Space Tabulation Method." Applied Sciences 9, no. 20 (October 18, 2019): 4408. http://dx.doi.org/10.3390/app9204408.
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A grating projection method is often used as a highly accurate 3D shape measurement method. A real-time 3D shape measurement system can also be applied to measure a wide and smooth curved surface, such as in sheet metal processing. In this case, operators take much effort to recognize the positions of some problem areas on an object from a measured result displayed on a monitor. This study develops a projection mapping system projecting an evaluation image, such as height, displacement, gradient, curvature factor, and area of defect, onto an object. These evaluation results are obtained from the measured 3D shape. The evaluation image should be deformed according to the 3D shape of the object because the camera and projector positions are different. Therefore, this study proposes a method to quickly produce a deformed evaluation image using a whole-space tabulation method. A coordinate transform table allowed the conversion of a camera pixel coordinate into a projector pixel coordinate by using reference planes to apply deformation to the evaluation image according to the measured 3D shape. The quick coordinate transformation from a camera pixel coordinate into a projector pixel coordinate was realized using the coordinate transform table. This is a key idea of this study. It was confirmed that the coordinate transformation from the camera pixel coordinate to the projector coordinate could be performed in 4.5 ms using the coordinate transform table. In addition, 3D shape measurement projection mapping was applied to a curved sheet metal with small deformation, and the deformation part was clearly shown by projecting the height distribution. The architecture and the experimental results are shown herein.
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Giachetti, A., and C. Lovato. "Radial Symmetry Detection and Shape Characterization with the Multiscale Area Projection Transform." Computer Graphics Forum 31, no. 5 (August 2012): 1669–78. http://dx.doi.org/10.1111/j.1467-8659.2012.03172.x.
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Tian, Xi Jie, Jing Yu, and Chang Chun Li. "Identification of the Hook on Investment Casting Shell Line Based on Machine Vision." Applied Mechanics and Materials 220-223 (November 2012): 1356–61. http://dx.doi.org/10.4028/www.scientific.net/amm.220-223.1356.
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In this paper, the idea identify the hook on investment casting shell line based on machine vision has been proposed. According to the characteristic of the hook, we do the image acquisition and preprocessing, we adopt Hough transform to narrow the target range, and find the target area based on the method combining the level projection and vertical projection, use feature matching method SIFT to do the image matching. Finally, we get the space information of the target area of the hook.
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Yan, Jin, Tiansheng Xu, Ni Li, and Guanghong Gong. "Regression and Evaluation on a Forward Interpolated Version of the Great Circle Arcs–Based Distortion Metric of Map Projections." ISPRS International Journal of Geo-Information 10, no. 10 (September 26, 2021): 649. http://dx.doi.org/10.3390/ijgi10100649.
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We studied the numerical approximation problem of distortion in map projections. Most widely used differential methods calculate area distortion and maximum angular distortion using partial derivatives of forward equations of map projections. However, in certain map projections, partial derivatives are difficult to calculate because of the complicated forms of forward equations, e.g., equations with iterations, integrations, or multi-way branches. As an alternative, the spherical great circle arcs–based metric employs the inverse equations of map projections to transform sample points from the projection plane to the spherical surface, and then calculates a differential-independent distortion metric for the map projections. We introduce a novel forward interpolated version of the previous spherical great circle arcs–based metric, solely dependent on the forward equations of map projections. In our proposed numerical solution, a rational function–based regression is also devised and applied to our metric to obtain an approximate metric of angular distortion. The statistical and graphical results indicate that the errors of the proposed metric are fairly low, and a good numerical estimation with high correlation to the differential-based metric can be achieved.
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Feng, Xiang, Yang-chun Song, Zhi-quan Zhou, and Yi-nan Zhao. "Designing Unimodular Waveform with Low Range Sidelobes and Stopband for Cognitive Radar via Relaxed Alternating Projection." International Journal of Antennas and Propagation 2016 (2016): 1–9. http://dx.doi.org/10.1155/2016/6280508.
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Cognitive radar could adapt the spectrum of waveforms in response to information regarding the changing environment, so as to avoid narrowband interference or electronic jamming. Besides stopband constraints, low range sidelobes and unimodular property are also desired. In this paper, we propose a Spectral Approximation Relaxed Alternating Projection (SARAP) method, to synthesize unimodular waveform with low range sidelobes and spectral power suppressed. This novel method, based on phase retrieval and relaxed alternating projection, could convert the correlation optimization into the spectrum approximation via the Fast Fourier Transform (FFT). Moreover, by virtue of the relaxation factor and accelerated factor, SARAP can exploit local area and more likely converge to the global solution. Numerical trials have demonstrated that SARAP could achieve excellent performance and computational efficiency which will facilitate the real-time design.
Dissertations / Theses on the topic "Area Projection Transform"
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LOVATO, Christian. "Three-dimensional body scanning: methods and applications for anthropometry." Doctoral thesis, 2013. http://hdl.handle.net/11562/540549.
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In questa tesi descriviamo i metodi informatici e gli esperimenti eseguiti per l’applicazione della tecnologia whole body 3D scanner in supporto dell’antropometria. I body scanner restituiscono in uscita una nuvola di punti, solitamente trasformata in mesh triangolare mediante l’uso di algoritmi specifici per supportare la visualizzazione 3D della superficie e l’estrazione di misure e landmarks antropometrici significativi. L’antropometria digitale è già stata utilizzata con successo in vari studi per valutare importanti parametri medici.
L’analisi antropometrica digitale è solitamente eseguita utilizzando soluzioni software fornite dai costruttori che sono chiuse e specifiche per il prodotto, che richiedono attenzione nell’acquisizione e dei forti limiti sulla posa assunta dal soggetto. Questo può portare a dei problemi nella comparazione di dati acquisiti in diversi luoghi, nella realizzazione di studi multicentrici su larga scala e nell’applicazione di metodi avanzati di shape analysis sui modelli acquisiti.
L’obiettivo del nostro lavoro è di superare questi problemi selezionando e personalizzando strumenti di processing geometrico capaci di creare un sistema aperto ed indipendente dallo strumento per l’analisi di dati da body scanner. Abbiamo inoltre sviluppato e validato dei metodi per estrarre automaticamente dei punti caratteristici, segmenti corporei e misure significative che possono essere utilizzate nella ricerca antropometrica e metabolica.
Nello specifico, presentiamo tre esperimenti. Nel primo, utilizzando uno specifico software per l’antropometria digitale, abbiamo valutato la performance dello scanner Breuckmann BodySCAN nelle misure antropometriche. I soggetti degli esperimenti sono 12 giovani adulti che sono stati sottoposti procedure di antropometria manuale e digitale tridimensionale (25 misurazioni) indossando abbigliamento intimo attillato. Le misure duplicate effettuate da un’antropometrista esperto mostrano una correlazione r=0.975-0.999; la loro media è significativamente (secondo il test t di Student) diversa su 4 delle 25 misure. Le misure digitali effettuate in duplicato da un antropometrista esperto e da due antropometristi non esperti, mostrano indici di correlazione individuali r che variano nel range 0.975-0.999 e medie che che erano significativamente diverse in una misurazione su 25. La maggior parte delle misure effettuate dall’antropometrista esperto, manuali e digitali, mostrano una correlazione significativa (coefficiente di correlazione intra-classe che variano nell’intervallo 0.855-0.995, p<0.0001). Concludiamo che lo scanner Breuckmann BodySCAN è uno strumento affidabile ed efficace per le misure antropometriche.
In un secondo esperimento, compariamo alcune caratteristiche geometriche facilmente misurabili ottenute dalle scansioni di femmine obese (BMI>30) con i parametri di composizione corporea (misurata con una DXA) dei soggetti stessi, per investigare quali misure dei descrittori di forma correlavano meglio con il grasso del torso e corporeo. I risultati ottenuti mostrano che alcuni dei parametri geometrici testati presentano una elevata correlazione, mentre altri non correlano fortemente con il grasso corporeo. Questi risultati supportano il ruolo dell’antropometria digitale nell’indagine sulle caratteristiche fisiche rilevanti per la salute, ed incoraggiano la realizzazione di ulteriori studi che analizzino la relazione tra descrittori di forma e composizione corporea.
Infine, presentiamo un nuovo metodo per caratterizzare le superfici tridimensionali mediante il calcolo di una funzione chiamata “Area projection transform”, la quale misura la possibilità dei punti dello spazio 3D di essere il centro di simmetria radiale della forma a predeterminati raggi. La trasformata può essere usata per rilevare e caratterizzare in maniera robusta i regioni salienti (approssimativamente parti sferiche e cilindriche) ed è, quindi, adatta ad applicazioni come la detection di caratteristiche anatomiche. In particolare, mostriamo che è possibile costruire grafi che uniscono questi punti seguendo i valori massimali della MAPT (Radial Simmetry Graphs) e che questi grafi possono essere usati per estrarre rilevanti proprietà della forma o definire corrispondenze puntuali robuste nei confronti di problematiche quali parti mancanti, rumore topologico e deformazioni articolate.
Concludiamo che le potenziali applicazioni della tecnologia della scansione tridimensionale applicata all’antropometria sono innumerevoli, limitate solo dall’abilità della conoscienza scientifica di connettere il fenomeno biologico con le appropriate descrizioni matematiche/geometriche.In this thesis we describe the developed computer method and experiments performed in order to apply whole body 3D scanner technology in support to anthropometry. The output of whole body scanners is a cloud of points, usually transformed in a triangulated mesh through the use of specific algorithms in order to support the 3D visualization of the surface and the extraction of meaningful anthropometric landmarks and measurements. Digital anthropometry has been already used in various studies to assess important health-related parameters. Digital anthropometric analysis is usually performed using device-specific and closed software solutions provided by scanner manufacturers, and requires often a careful acquisition, with strong constraints on subject pose. This may create problems in comparing data acquired in different places and performing large-scale multi-centric studies as well as in applying advanced shape analysis tools on the captured models. The aim of our work is to overcome these problems by selecting and customizing geometrical processing tools able to create an open and device-independent method for the analysis of body scanner data. We also developed and validated methods to extract automatically feature points, body segments and relevant measurements that can be used in anthropometric and metabolic research. In particular we present three experiments. In the first, using specific digital anthropometry software, we evaluated the Breuckmann BodySCAN for performance in anthropometric measurement. Subjects of the experiment were 12 young adults underwent both manual and 3D digital anthropometry (25 measurements) wearing close-fitting underwear. Duplicated manual measurement taken by one experienced anthropometrist showed correlation r 0.975-0.999; their means were significantly different in four out of 25 measurements by Student’s t test. Duplicate digital measurements taken by one experienced anthropometrist and two naïve anthropometrists showed individual correlation coefficients r ranging 0.975-0.999 and means were significantly different in one out of 25 measurements. Most measurements taken by the experienced anthropometrist in the manual and digital mode showed significant correlation (intraclass correlation coefficient ranging 0.855-0.995, p<0.0001). We conclude that the Breuckmann BodyScan is reliable and effective tool for digital anthropometry. In a second experiment, we compare easily detectable geometrical features obtained from 3D scans of female obese (BMI > 30) subjects with body composition (measured with a DXA device) of the same subjects, in order to investigate which measurements on shape descriptors better correlate with torso and body fat. The results obtained show that some of the tested geometrical parameters have a relevant correlation, while other ones do not strongly correlate with body fat. These results support the role of digital anthropometry in investigating health-related physical characteristics and encourage the realization of further studies analyzing the relationships between shape descriptors and body composition. Finally, we present a novel method to characterize 3D surfaces through the computation of a function called Area Projection Transform, measuring the likelihood of points in the 3D space to be center of radial symmetry at selected scales (radii). The transform can be used to detect and characterize robustly salient regions (approximately spherical and cylindrical parts) and it is, therefore, suitable for applications like anatomical features detection. In particular, we show that it is possible to build graphs joining these points following maximal values of the MAPT (Radial Symmetry Graphs) and that these graphs can be used to extract relevant shape properties or to establish point correspondences on models robustly against holes, topological noise and articulated deformations. It is concluded that whole body scanning technology application to anthropometry are potentially countless, limited only by the ability of science to connect the biological phenomenon with the appropriate mathematical/geometrical descriptions.
Books on the topic "Area Projection Transform"
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Huybrechts, D. Fourier–Mukai Transforms. Oxford University Press, 2007. http://dx.doi.org/10.1093/acprof:oso/9780199296866.003.0005.
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This chapter introduces the central notion of a Fourier-Mukai transform between derived categories. It is the derived version of the notion of a correspondence, which has been studied for all kinds of cohomology theories for many decades. In fact, Orlov's celebrated result, which is stated but not proved, says that any equivalence between derived categories of smooth projective varieties is of Fourier-Mukai type. Fourier-Mukai functors behave well in many respects: they are exact, admit left and right adjoints, can be composed, etc. The cohomological Fourier-Mukai transform behaves with respect to grading, Hodge structure, and Mukai pairing.
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Huybrechts, D. Fourier-Mukai Transforms in Algebraic Geometry. Oxford University Press, 2007. http://dx.doi.org/10.1093/acprof:oso/9780199296866.001.0001.
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This book provides a systematic exposition of the theory of Fourier-Mukai transforms from an algebro-geometric point of view. Assuming a basic knowledge of algebraic geometry, the key aspect of this book is the derived category of coherent sheaves on a smooth projective variety. The derived category is a subtle invariant of the isomorphism type of a variety, and its group of autoequivalences often shows a rich structure. As it turns out — and this feature is pursued throughout the book — the behaviour of the derived category is determined by the geometric properties of the canonical bundle of the variety. Including notions from other areas, e.g., singular cohomology, Hodge theory, abelian varieties, K3 surfaces; full proofs and exercises are provided. The final chapter summarizes recent research directions, such as connections to orbifolds and the representation theory of finite groups via the McKay correspondence, stability conditions on triangulated categories, and the notion of the derived category of sheaves twisted by a gerbe.
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Gamberini, Andrea. Rural Communes and the Culture of Practices. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780198824312.003.0012.
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The projection of city-state political culture on to the surrounding countryside did not only generate forms of resistance from and misunderstanding with local society. This chapter shows how certain social and political actors active in rural areas managed to exploit urban political and legal culture, bending it to their own interests. In other words, the advent of city domination created new possibilities, especially those linked to the activity of the communal courts, which could transform the claims of certain countryside figures into concrete rights. The chapter offers an analysis of several of these situations, in order to provide a clearer understanding of the relationship between city and countryside.
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Tretkoff, Paula. Complex Surfaces and Coverings. Princeton University Press, 2017. http://dx.doi.org/10.23943/princeton/9780691144771.003.0004.
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This chapter deals with complex surfaces and their finite coverings branched along divisors, that is, subvarieties of codimension 1. In particular, it considers coverings branched over transversally intersecting divisors. Applying this to linear arrangements in the complex projective plane, the chapter first blows up the projective plane at non-transverse intersection points, that is, at those points of the arrangement where more than two lines intersect. These points are called singular points of the arrangement. This gives rise to a complex surface and transversely intersecting divisors that contain the proper transforms of the original lines. The chapter also introduces the divisor class group, their intersection numbers, and the canonical divisor class. Finally, it describes the Chern numbers of a complex surface in order to define the proportionality deviation of a complex surface and to study its behavior with respect to finite covers.
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Kondapalli, Srikanth. China’s Evolving Naval Presence in the Indian Ocean Region. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780199479337.003.0007.
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In this chapter, the author examines the various elements of China’s security presence in the Indian Ocean. He argues that while a ‘flag-following-trade’ policy was visible earlier, China’s policy today is to influence the structure of maritime power in the Indian Ocean region through strengthening its offshore defence capabilities. This involves the development of semi-military alliances, dual-use port facilities, stationing of non-combat troops initially abroad, Military Operations Other Than War (MOOTW) missions and arms transfers to the region. He concludes that while China has succeeded in entering into the Indian Ocean region, it faces formidable challenges from the United States, India and others and the limitations on China’s power projection capabilities are becoming increasingly clear.
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Bullock, Barbara E., Lars Hinrichs, and Almeida Jacqueline Toribio. World Englishes, Code-Switching, and Convergence. Edited by Markku Filppula, Juhani Klemola, and Devyani Sharma. Oxford University Press, 2014. http://dx.doi.org/10.1093/oxfordhb/9780199777716.013.009.
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In this chapter, it is argued that the study of World Englishes (WE) should assume a more central place in the analysis of variation and change in the context of language contact. Because they emerge from situations of bilingualism and contact, WE varieties are highly informative with regard to the structural issues of code-switching and convergence (also termed structural borrowing, transfer, interference, imposition). The inherently mixed nature of WE is shown here to mirror the diverse structural patterns that are commonly encountered in bilingual speech. It is argued that different mixing patterns arise in response to the social and medial embedding of WE vernaculars at the community, the individual, and the interactional levels. Social evaluations of relative prestige, individual projections of style, stance, and identity, and the complex nature of multilingual interaction conspire to bring about complex, new language structures.
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Marks II, Robert J. Handbook of Fourier Analysis & Its Applications. Oxford University Press, 2009. http://dx.doi.org/10.1093/oso/9780195335927.001.0001.
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Fourier analysis has many scientific applications - in physics, number theory, combinatorics, signal processing, probability theory, statistics, option pricing, cryptography, acoustics, oceanography, optics and diffraction, geometry, and other areas. In signal processing and related fields, Fourier analysis is typically thought of as decomposing a signal into its component frequencies and their amplitudes. This practical, applications-based professional handbook comprehensively covers the theory and applications of Fourier Analysis, spanning topics from engineering mathematics, signal processing and related multidimensional transform theory, and quantum physics to elementary deterministic finance and even the foundations of western music theory. As a definitive text on Fourier Analysis, Handbook of Fourier Analysis and Its Applications is meant to replace several less comprehensive volumes on the subject, such as Processing of Multifimensional Signals by Alexandre Smirnov, Modern Sampling Theory by John J. Benedetto and Paulo J.S.G. Ferreira, Vector Space Projections by Henry Stark and Yongyi Yang and Fourier Analysis and Imaging by Ronald N. Bracewell. In addition to being primarily used as a professional handbook, it includes sample problems and their solutions at the end of each section and thus serves as a textbook for advanced undergraduate students and beginning graduate students in courses such as: Multidimensional Signals and Systems, Signal Analysis, Introduction to Shannon Sampling and Interpolation Theory, Random Variables and Stochastic Processes, and Signals and Linear Systems.
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Tércio, Daniel, ed. TEPe 2022 - Encontro Internacional sobre a Cidade, o Corpo e o Som. INET-md, Faculdade de Motricidade Humana, Universidade de Lisboa, 2022. http://dx.doi.org/10.53072/ilic8040.
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Os contextos pandémico e pós-pandémico vêm impondo às cidades outras dinâmicas, outros sons, outros ecos, outros percursos, outros visitantes humanos e não humanos. Durante o confinamento, o encerramento de espaços teatrais e expositivos – bem como, durante o desconfinamento, as limitações para a sua utilização - têm tido consequências penosas nas programações artísticas e efeitos dramáticos nos quotidianos dos seus agentes (artistas, técnicos, programadores, curadores, etc.). Ao mesmo tempo, a desaceleração da vida da cidade (do trânsito, do ritmo nas ruas, do frenesim produtivo e de consumo, etc.) veio contribuir beneficamente para uma diminuição das emissões de CO2. Neste quadro, a cidade - mais concretamente as suas zonas públicas a céu aberto – surgem mais nitidamente como espaços de circulação e de interferência (ou de suspensão de interferência) entre pessoas. O que aprendemos com a experiência de confinamento e desconfinamento? Em primeiro lugar, que a cidade tem uma densidade flutuante, na medida em que as concentrações populacionais se esvaem quando nos encerramos em casa. Em segundo lugar, que o encontro com o outro (uma das prerrogativas da cidade) pode acontecer em outras escalas que não apenas a dimensão cultural. Em terceiro lugar, que o medo pode ser um sentimento público capaz de fazer implodir as próprias cidades, se não for transformado numa força para a vida. Como é que, neste processo, os artistas se organizam e se constituem como agentes na cidade? Como é que a cidade passou a ser representada? Que cidade é aquela que desejamos? Este congresso surge assim da necessidade de intensificar o diálogo entre a cidade e a arte, em particular as artes performativas. Este encontro efoi o culminar de dois anos de investigação consistente e consolidada no âmbito do projecto TEPe (Technologically Expanded Performance). Ao longo destes dois anos, desenvolvemos atividades com a comunidade com o intuito de promover um diálogo intercultural e transdisciplinar, e proporcionar o encontro com vivências urbanas variadas. Através das diferentes propostas de percursos pela cidade, mapeámos acontecimentos, hoje invisíveis, mas ainda assim presentes: desde “memórias soterradas” a “caminhadas sensoriais”, passando por registos íntimos de confinamento. O encontro visou partilhar as experiências realizadas com a contribuição de duas equipas: a portuguesa, em Lisboa, e a brasileira, em Fortaleza. Para além de apresentarmos as conclusões das pesquisas realizadas, lançamos esta chamada para apresentações, especialmente destinada a artistas e estudiosos de performance art, historiadores das cidades, antropólogos, urbanistas, geógrafos, estudiosos da escuta e do som e a todxs aquelxs a quem interessa pensar (e projectar) a vida na cidade. -------------------------------------------------------------------------------------------------------------- The pandemic and post-pandemic contexts have imposed on cities other dynamics, other sounds, other echoes, other routes, other human and non-human visitors. During the lockdown, the closure of theatrical and exhibition spaces - as well as, during lockdown unlocking, the limitations for their use - have had painful consequences in artistic programming and dramatic effects in the daily lives of its agents (artists, technicians, programmers, curators, etc.). At the same time, the slowing down of city life (traffic, the pace of the streets, the frenzy of production and consumption, etc.) has made a beneficial contribution to a reduction in CO2 emissions. In this context, the city - and more specifically its open-air public areas - emerge more clearly as spaces for circulation and interference (or suspension of interference) between people. What have we learned from the experience of national lockdown and unlocking? Firstly, that the city has a fluctuating density, insofar as population concentrations fade when we shut ourselves indoors. Secondly, the encounter with the other (one of the prerogatives of the city) can take place on other scales than the cultural dimension alone. Thirdly, fear can be a public sentiment capable of imploding cities themselves if it is not transformed into a force for life. How, in this process, are artists organised and constituted as agents in the city? How did the city come to be represented? What kind of city do we want? This congress thus arises from the need to intensify the dialogue between the city and art, particularly the performing arts. This international meeting is the culmination of two years of consistent and consolidated research within the TEPe (Technologically Expanded Performance) project. Throughout these two years, we have developed activities with the community to promote intercultural and transdisciplinary dialogue and provide an encounter with varied urban experiences. Through the different proposals of walks through the city, we have mapped events, today invisible, but still present: from "buried memories" to "sensorial walks", passing through intimate records of confinement. The meeting aims to share the experiences carried out with the contribution of two teams: the Portuguese, in Lisbon, and the Brazilian, in Fortaleza. Besides presenting the conclusions of the researches carried out, we launch this call for presentations, especially addressed to artists and scholars of performance art, historians of cities, anthropologists, urban planners, geographers, scholars of listening and sound and to all those who are interested in thinking (and projecting) life in the city.
Book chapters on the topic "Area Projection Transform"
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Cook, A., O. Rondon, J. Graindorge, and G. Booth. "Iterative Gaussianisation for Multivariate Transformation." In Springer Proceedings in Earth and Environmental Sciences, 21–35. Cham: Springer International Publishing, 2023. http://dx.doi.org/10.1007/978-3-031-19845-8_2.
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AbstractMultivariate conditional simulations can be reduced to a set of independent univariate simulations through multivariate Gaussian transformation of the drill hole data to independent Gaussian factors. These simulations are then back transformed to obtain simulated results that exhibit the multivariate relationships observed in the input drill hole data. Several transformation techniques are cited in geostatistical literature for multivariate transformation. However, only two can effectively simulate high dimensional drill hole data with complex non-linear features: Flow Anamorphosis (FA) and Projection Pursuit Multivariate Transformation (PPMT). This paper presents an alternative iterative multivariate Gaussian transformation (IG) along with a multivariate simulation case study of a large Nickel deposit. Our findings show that IG is computationally faster than FA and PPMT which makes the technique more appealing for most practical and time-sensitive applications.
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Eshel, Gidon. "Empirical Orthogonal Functions." In Spatiotemporal Data Analysis. Princeton University Press, 2011. http://dx.doi.org/10.23943/princeton/9780691128917.003.0011.
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This chapter focuses on empirical orthogonal functions (EOFs). One of the most useful and common eigen-techniques in data analysis is the construction of EOFs. EOFs are a transform of the data; the original set of numbers is transformed into a different set with some desirable properties. In this sense the EOF transform is similar to other transforms, such as the Fourier or Laplace transforms. In all these cases, we project the original data onto a set of functions, thus replacing the original data with the set of projection coefficients on the chosen new set of basis vectors. However, the choice of the specific basis set varies from case to case. The discussions cover data matrix structure convention, reshaping multidimensional data sets for EOF analysis, forming anomalies and removing time mean, missing values, choosing and interpreting the covariability matrix, calculating the EOFs, projection time series, and extended EOF analysis.
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Walley, Jonathan. "Cinema as Performance." In Cinema Expanded, 157–253. Oxford University Press, 2020. http://dx.doi.org/10.1093/oso/9780190938635.003.0004.
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Chapter 3 is the first of four chapters that make up Part II of Cinema Expanded. This part of the book considers different general modes that expanded cinema has taken, each mode representing aesthetic territory and ideas usually associated with a different art form (e.g. performance or sculpture). Chapter 3 considers a variant of expanded cinema that integrates live performance into projection of moving images, usually called “projection performance” or “projector performance.” In this type of expanded work, the tactility of both filmstrip and projector are on display, as is the performer (typically the filmmaker—the representative of avant-garde cinema’s more intimate relationship between artist and audience). But alongside these markers of cinema’s physicality and presence is the ephemerality of live performance. Non-repeatable, site-specific, aleatory instead of mechanistically automatic, projection performance is centered upon the moment when the material of film is transformed into the far less tactile play of light, shadow, and illusion, and when objects give way to processes and experiences. The integration of performance into cinema was initially understood as a blurring of art forms. But the intermedia film-theater hybrids of the first wave of expanded cinema gave way to subsequent projection performances that claimed a performative dimension for cinema itself, rather than thinking of it as an alien form grafted onto film in a new intermedia format.
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Kang, Yiyun. "Casting." In Practices of Projection, 193–210. Oxford University Press, 2020. http://dx.doi.org/10.1093/oso/9780190934118.003.0012.
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This chapter investigates how projection mapping reconfigures the relationship between projection surface, moving image, and space in the field of artists’ projected moving-image works. Projection mapping is a relatively new method that can be used to transform irregularly shaped objects and indoor/outdoor spaces into display surfaces. This mode of projection envelops three-dimensional surfaces with digital moving images, using complicated projection technologies. In examining this process, the author analyses various contextual reviews as well as her own piece Casting to discover projection mapping’s distinctive properties. Casting (2016) is Kang’s projection-mapping installation at the Victoria and Albert Museum (V&A) in London, which was created as the culmination of Kang’s six-month artist-in-residency program at the V&A, and acquired by the institution in 2017 as its first purchase of a projection-mapping installation piece. This chapter examines how, by integrating volumetric objects and space, projection mapping dismantles the conventional notion of screen and frame that are accepted in experimental film and video installation works. The chapter introduces the concept of augmented space to understand how the spatial employment of projected moving images generates a novel type of narrative and experiences in comparison with the previous projected moving-image artworks. Accordingly, the chapter identifies how projection mapping practices can develop a distinguished type of aura in the realm of digital media art works.
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Li, Bingcheng. "Time Frequency Analysis for Radio Frequency (RF) Signal Processing." In Recent Advances of Wavelet Transform and Their Applications [Working Title]. IntechOpen, 2022. http://dx.doi.org/10.5772/intechopen.102821.
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In high-density radio frequency (RF) signal environments, receivers usually acquire signals from multiple sources. These RF signals may be co-channel and co-duration, which cause significant difficulties for processing them. Time-Frequency analysis combined with a projection pursuits graph approach provides an effective way to detect, separate, and classify these multiple source RF signals. Time-frequency analysis includes a spectrogram approach and a scalogram approach. The feature points on the instantaneous frequency function of a frequency modulation radio frequency (FMRF) signal can be extracted from either the spectrogram or scalogram of this FMRF signal. With the projection pursuits graph approach, these feature points are grouped into time-frequency functions to represent the multiple components for the separation, detection, and classification of this multisource FMRF signal.
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Sugimoto, Masanori. "Projected Displays of Mobile Devices for Collaboration." In Handbook of Research on User Interface Design and Evaluation for Mobile Technology, 594–607. IGI Global, 2008. http://dx.doi.org/10.4018/978-1-59904-871-0.ch035.
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Mobile devices have so far been personal tools. With their evolution of increased functionality, however, these devices have begun to be used in a shared fashion by multiple people. This chapter discusses techniques allowing multiple people to share mobile devices by projecting their displays and conducting intuitive manipulations on them. The chapter first shows overviews of systems and technologies related to location-aware projection and several interaction techniques. Then, a system called Hotaru that implements intuitive manipulation techniques on projected displays of multiple mobile devices is described. Hotaru allows a user to annotate or rotate a picture or a document on a projected display by using his finger and intuitively to transfer a file between multiple devices by overlapping their projected displays. User studies of Hotaru indicated that the proposed manipulation techniques could support multiple people in a single location in conducting their tasks. Research issues on projected displays of mobile devices are raised.
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Motornyuk, Ruslan Leonidovich, and Stepan Mykolayovych Bilan. "The Moving Object Detection and Research Effects of Noise on Images Based on Cellular Automata With a Hexagonal Coating Form and Radon Transform." In Handbook of Research on Intelligent Data Processing and Information Security Systems, 330–59. IGI Global, 2020. http://dx.doi.org/10.4018/978-1-7998-1290-6.ch013.
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Methods for image identification based on the Radon transform using hexagonal-coated cellular automata in the chapter are considered. A method and a mathematical model for the detection of moving objects based on hexagonal-coated cellular automata are described. The advantages of using hexagonal coverage for detecting moving objects in the image are shown. The technique of forming Radon projections for moving regions in the image, which is designed for a hexagonal-coated cellular automata, is described. The software and hardware implementation of the developed methods are presented. Based on the obtained results, a hexagonal-coated cellular automata was developed to identify images of objects based on the Radon transform. The Radon transform allowed to effectively extract the characteristic features of images with a large percentage of noise. Experimental analysis showed the advantages of the proposed methods of image processing and identification of moving objects.
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Delello, Julie A., and Rochell R. McWhorter. "New Visual Social Media for the Higher Education Classroom." In The Social Classroom, 368–93. IGI Global, 2014. http://dx.doi.org/10.4018/978-1-4666-4904-0.ch019.
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This chapter examines how next-generation visual social platforms motivate students to capture authentic evidence of their learning and achievements, publish digital artifacts, and share content across visual social media. Educators are facing the immediate task of integrating social media into their current practice to meet the needs of the twenty-first century learner. Using a case study, this chapter highlights through empirical work how nascent visual social media platforms such as Pinterest are being utilized in the college classroom and concludes with projections on ways visual networking platforms will transform traditional models of education.
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Manuel Velazquez Arcos, Juan, Ricardo Teodoro Paez Hernandez, Alejandro Perez Ricardez, Jaime Granados Samaniego, and Alicia Cid Reborido. "On the Zap Integral Operators over Fourier Transforms." In Real Perspective of Fourier Transforms and Current Developments in Superconductivity. IntechOpen, 2021. http://dx.doi.org/10.5772/intechopen.94573.
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We devote the current chapter to describe a class of integral operators with properties equivalent to a killer operator of the quantum mechanics theory acting over a determined state, literally killing the state but now operating over some kind of Fourier integral transforms that satisfies a certain Fredholm integral equation, we call this operators Zap Integral Operators (ZIO). The result of this action is to eliminate the inhomogeneous term and recover a homogeneous integral equation. We show that thanks to this class of operators we can explain the presence of two extremely different solutions of the same Generalized Inhomogeneous Fredholm equation. So we can regard the Generalized Inhomogeneous Fredholm Equation as a Super-Equation with two kinds of solutions, the resonant and the conventional but coexisting simultaneously. Also, we remember the generalized projection operators and we show they are the precursors of the ZIO. We present simultaneous academic examples for both kinds of solutions.
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Rolls, Edmund T. "The olfactory system." In Brain Computations, 217–31. Oxford University Press, 2020. http://dx.doi.org/10.1093/oso/9780198871101.003.0005.
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There are 1000 gene-specified olfactory receptor types projecting to the olfactory bulb and then to the olfactory (pyriform) cortex. This processing enables what the odour is to be represented. The olfactory (pyriform) cortex then projects to the orbitofrontal cortex, where the representation is mapped away from a gene-specified space into an odour reward value space, with the orbitofrontal cortex responding for example to the pleasantness of odours including the smell and flavour of food. The mechanism of the transform includes pattern association with stimuli in other modalities, such as the taste and texture of food.
Conference papers on the topic "Area Projection Transform"
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Xiang-yang, Yang, Wu Min-shian, and Chin Kuo-fan. "Measuring Two Dimensional OTF Applying CT Principle." In Optical Data Storage. Washington, D.C.: Optica Publishing Group, 1985. http://dx.doi.org/10.1364/ods.1985.thdd3.
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In optical disc system, the precise measurement and evaluation of focused micro-laser-spot (usually less than lum in diameter) is very important. To meet this requirement, a new method using the concept of CT scanner has been developed. A knife-edge scans the spot on the image plane. Differentiating the signal received by the detecter under the knife-edge, we get a one-dimension (1-D) projection of 2-D laser spot. Rotating the knife-edge slightly, we can get different projections at different angles. The projections measured are processed by taking the convolution and back-projecttion, just done as in the CT scanner. In this way, we get the 2-D profiles of the spot, i.e. the Point Spread Function (PSF) of the optical head. The shape and size of the spot can be got directly from the profile. The 2-D Fourier Transform of PSF results in the OTF of the optical head, which discribes the quality of the optical system quantitatively.
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Singh, Dhruv, Atul Srivastava, and K. Muralidhar. "Tomographic Reconstruction of Unsteady Fields Using Proper Orthogonal Decomposition." In ASME 2008 Heat Transfer Summer Conference collocated with the Fluids Engineering, Energy Sustainability, and 3rd Energy Nanotechnology Conferences. ASMEDC, 2008. http://dx.doi.org/10.1115/ht2008-56443.
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An algorithm for the reconstruction of unsteady three dimensional concentration field from path-integrated data has been discussed. We propose the use of Proper Orthogonal Decomposition (Karhunen Loe´ve Expansion) to completely decouple the spatial and temporal components of the image sequence (projections) obtained from a typical experiment enabling the analysis of an asynchoronous time-dependent data set. We apply the algorithm to experimental data from a Laser Interferometric study of convection in a cylindrical annulus to capture transients that are invariably faster than the camera speed. The strength of the technique is demonstrated in the reconstruction of the flow field (related to concentration gradients) from model (simulated) Schlieren projections. Tomographic reconstruction based on Convolution Back Projection (CBP) has been coupled with Proper Orthogonal Decomposition to enable the reconstruction of unsteady concentration gradient field from asynchronous projections.
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Neureuther, A. R. "Application of Lithography Simulation to Projection X-Ray." In Soft X-Ray Projection Lithography. Washington, D.C.: Optica Publishing Group, 1993. http://dx.doi.org/10.1364/sxray.1993.ma.5.
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Simulators and materials modeling approaches from optical projection printing provide an advantageous starting point in addressing technology issues in the emerging field of projection x-ray lithography. A brief overview will be given of relevant imaging, resist characterization, resist exposure, resist dissolution, pattern transfer, and electromagnetic scattering programs available from Berkeley. The overview will also highlight important observations drawn from simulation and modeling which are helping optical projection printing at todays 0.35 um feature sizes. Key issues in projection x-ray lithography imaging, materials, and masks where these Technology CAD tools are making an impact will then be discussed.
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Chen, Shisheng, Xiaofang Wang, Aidi Qian, and Zhizhan Xu. "Soft-X-Ray Emission Characteristics of Line-Shaped, Laser-Produced Plasmas." In Soft X-Ray Projection Lithography. Washington, D.C.: Optica Publishing Group, 1991. http://dx.doi.org/10.1364/sxray.1991.wa12.
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Line-shaped plasmas produced by laser irradiating solid targets in line focus are of a large aspect ratio. Such plasmas are useful for x-ray laser demonstration and amplification and absorption spectroscopy as well. Soft x rays emitted from line-shaped plasmas can provide accurate information of such plasmas. Here, we report the studies of x-ray radiation transfer and spatial uniformity of line-shaped plasmas with a pinhole transmission grating spectrometer (PTGS), with a spectral resolution of 2-5 Å and a spatial resolution of 60 µm, and a soft-x-ray streak camera, with a time resolution of 30 ps.
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Carruthers, John R. "Future Lithographic Requirements." In Soft X-Ray Projection Lithography. Washington, D.C.: Optica Publishing Group, 1993. http://dx.doi.org/10.1364/sxray.1993.ma.1.
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The future manufacture of IC's beyond 2000 will require pattern transfer systems of considerable complexity and cost. Critical dimensions below 150 nm must be controlled in three dimensions without interference from proximity effects and with an overlay/alignment capability that approaches 50 nm (3 sigma) from layer to layer over larger field sizes of 25 to 30 mm on a side. The metrology to develop and control these systems also needs to be developed with precision approaching atomic dimensions. The implications of these requirements on continuing the scaling treadmill approach for ULSI development are discussed.
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Brophy, Chris P. "Phase-shifting fringe-projection profile accuracy." In OSA Annual Meeting. Washington, D.C.: Optica Publishing Group, 1989. http://dx.doi.org/10.1364/oam.1989.tuu25.
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The performance of a commercial optical contouring system is presented. The AMMON 2000, an optical casting system that is used to contour the bottom of the human foot for the podiatry industry, incorporates a phase-shifting fringe-projection profiler. The height profile data, z(x, y), measured with the instrument, are used to automatically design and surface a correcting orthotic. Data reduction software accounts for geometric distortions that are intrinsic to fringe projection topography when generated with a nontelecentric optical system. Contributions to the distortion that are due to the finite distance of the camera and projector exit pupils are detailed. By knowing the various parameters associated with the optical setup, as well as the position of a single reference point on the object, found by some other means, it is theoretically possible to transform the raw OPD data to the desired height contour, z(x, y), with absolute accuracy. In the AMMON 2000 the reference point is obtained by viewing the object at an angle that is nearly orthogonal to the projection axis.
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Kunz, R. R., M. A. Hartney, and M. Rothschild. "Resist Alternatives for Sub-0.35-μm Lithography Using Highly Attenuated Radiation." In Soft X-Ray Projection Lithography. Washington, D.C.: Optica Publishing Group, 1992. http://dx.doi.org/10.1364/sxray.1992.wc1.
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Traditional optical lithography uses semitransparent single-layer resists where the exposing radiation produces a latent image throughout the thickness of the resist, and an isotropic liquid-based development step is used to create the desired resist profile. However, resolution of 0.25-μm or better, which is required for 256 Mbit DRAM chips and beyond, cannot be obtained with conventional photolithographic technology (250-400 nm wavelength). Shorter wavelengths are required, such as 193-nm (DUV-193), soft-X- ray (10-50 nm) or hard-X-ray (1-2 nm) radiation. Unfortunately, between the wavelengths of 10 and 220 nm few materials are semitransparent For example, at 193 nm novolac resins commonly used at longer wavelengths have an absorption depth of only 40 nm, and at the 13-nm wavelength it is 400 nm. New resist processes capable of accommodating a latent image confined to the near-surface region must therefore be developed. The lithographic process must now include an additional processing step, namely pattern transfer into the bulk of the resist. This step must be highly anisotropic so that the pattern in the surface layer is faithfully reproduced at the resist-substrate interface. These general considerations were outlined already in 1984 by Taylor et al.[1]. They apply also to other forms of strongly absorbed radiation such as ion beams. (For instance, a 30 keV Ga+ beam has a projected range of only 34 nm in photoresist.) Today, surface imaging processes have been demonstrated not only for soft X-ray projection (SXP) [2] and deep ultraviolet (DUV) lithographies [3], but are being considered for manufacturing processes at optical wavelengths as well [4]. In this paper we review some of the recent developments in the areas of surface imaging and multilayer resists, with emphasis on application to 193-nm lithography. It should be noted, however, that some of the reviewed resist concepts may be applicable to SXP lithography as well.
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MacDowell, A. A., O. R. Wood, J. M. Calvert, and T. S. Koloski. "A New Surface Imaging Resist Technology for Soft-X-Ray Projection Lithography." In Soft X-Ray Projection Lithography. Washington, D.C.: Optica Publishing Group, 1993. http://dx.doi.org/10.1364/sxray.1993.tua.5.
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Sub-quarter-micron features have been produced in a number of organic resists using soft-x-ray projection lithography (SXPL) at 14 nm, including a demonstration of 0.05 um lines and spaces in poly (methylmethacrylate) (PMMA).1 Unfortunately, the opacity of conventional resists in the soft-x-ray region requires that the resist thickness be reduced to less than 200 nm;2 in practice, 70 nm thick layers are often used. Such thin layers lead to several problems. First, spincoating pinhole-free layers becomes increasingly difficult at thicknesses below 100 nm. Second, the etch resistance of thin organic layers may not be sufficient for subsequent pattern transfer operations. Third, they are too thin to function as planarizing layers over preexisting substrate topography. One solution has been to use a trilevel resist composed of a thin top PMMA imaging layer, an intermediate layer of germanium for etch resistance, and a thick hardbaked photoresist for planarization. While the trilevel approach has been successfully demonstrated for producing high resolution features with SXPL at 14 nm,3 the complexity of this process makes it problematic for rapid acceptance in a production environment. An alternative approach, which circumvents the resist opacity issue, involves the use of so-called surfaceimaging resists.4 In a surface imaging resist, radiation-induced changes in a thin imaging layer lead to conversion of the exposed region to an etch resistant material.
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Wu, Xiao, Ting-Zhu Huang, Liang-Jian Deng, and Tian-Jing Zhang. "A Decoder-free Transformer-like Architecture for High-efficiency Single Image Deraining." In Thirty-First International Joint Conference on Artificial Intelligence {IJCAI-22}. California: International Joint Conferences on Artificial Intelligence Organization, 2022. http://dx.doi.org/10.24963/ijcai.2022/205.
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Despite the success of vision Transformers for the image deraining task, they are limited by computation-heavy and slow runtime. In this work, we investigate Transformer decoder is not necessary and has huge computational costs. Therefore, we revisit the standard vision Transformer as well as its successful variants and propose a novel Decoder-Free Transformer-Like (DFTL) architecture for fast and accurate single image deraining. Specifically, we adopt a cheap linear projection to represent visual information with lower computational costs than previous linear projections. Then we replace standard Transformer decoder block with designed Progressive Patch Merging (PPM), which attains comparable performance and efficiency. DFTL could significantly alleviate the computation and GPU memory requirements through proposed modules. Extensive experiments demonstrate the superiority of DFTL compared with competitive Transformer architectures, e.g., ViT, DETR, IPT, Uformer, and Restormer. The code is available at https://github.com/XiaoXiao-Woo/derain.
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Zhang, Juntao, and Raj M. Manglik. "Numerical Investigation of Single Bubble Dynamics During Nucleate Boiling in Aqueous Surfactant Solutions." In ASME 2003 Heat Transfer Summer Conference. ASMEDC, 2003. http://dx.doi.org/10.1115/ht2003-47047.
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The dynamics of a single growing and departing bubble during nucleate boiling from a horizontal heated surface in an aqueous surfactant solution has been numerically simulated. The full Navier-Stokes equations together with the bulk transport and adsorption-desorption-controlled surfactant interfacial transport equations are solved. A PDE-based fast local level-set method is used to computationally capture the vapor-liquid interface, and the dynamic surface tension is modeled as a body force on the interface. A second-order projection method along with a third-order ENO (essentially non-oscillatory) scheme for differencing the convection terms are applied for solving the momentum equation. The time discretization is dealt with a high order Runge-Kutta method. The multigrid preconditioned conjugate method (MPCG) is employed to solve the projection, which has strongly discontinuous coefficients caused by the physical properties jump across the vapor-liquid interface. The results illustrate the altered bubble dynamics in aqueous surfactant solutions, and their role in enhancing heat transfer.
Reports on the topic "Area Projection Transform"
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Asian Development Outlook 2021 Update: Transforming Agriculture in Asia. Asian Development Bank, September 2021. http://dx.doi.org/10.22617/fls210352-3.
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This report forecasts growth in developing Asia of 7.1% in 2021 and 5.4% in 2022 in an uneven recovery caused by divergent growth paths. Its theme chapter explores sustainable agriculture. Growth forecasts are revised up for East Asia and Central Asia from the projections made in April, but down for South Asia, Southeast Asia, and the Pacific. This reflects differences in vaccination progress and control of domestic COVID-19 outbreaks but also other factors, including rising commodity prices and depressed tourism. Inflation is expected to remain under control. The main risks to the economic outlook come from the COVID-19 pandemic, including the emergence of new variants, slower-than-expected vaccine rollouts, and waning vaccine effectiveness. Sustainable food production and agricultural systems that are resilient to climate change will be crucial for developing Asia. To transform agriculture in the region, its economies must tackle challenges from changing consumer demand, changing demographics, and a changing and more fragile environment.